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1207

Amino acid

Amino acids are organic compounds containing amine (-NH) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen, although other elements are found in the side chains of certain amino acids. About 500 amino acids are known (though only 20 appear in the genetic code) and can be classified in many ways. They can be classified according to the core structural functional groups' locations as alpha- (α-), beta- (β-), gamma- (γ-) or delta- (δ-) amino acids; other categories relate to polarity, pH level, and side chain group type (aliphatic, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid residues form the second-largest component (water is the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis.

1208

Alan Turing

Alan Mathison Turing ( ; 23 June 1912 – 7 June 1954) was an English computer scientist, mathematician, logician, cryptanalyst, philosopher and theoretical biologist.

1209

Area

Area is the quantity that expresses the extent of a two-dimensional figure or shape, or planar lamina, in the plane. Surface area is its analog on the two-dimensional surface of a three-dimensional object. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat. It is the two-dimensional analog of the length of a curve (a one-dimensional concept) or the volume of a solid (a three-dimensional concept).

1210

Astronomical unit

The astronomical unit (symbol: au or ua) is a unit of length, roughly the distance from Earth to the Sun. However, that distance varies as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once a year. Originally conceived as the average of Earth's aphelion and perihelion, it is now defined as exactly metres (about 150 million kilometres, or 93 million miles). The astronomical unit is used primarily as a convenient yardstick for measuring distances within the Solar System or around other stars. However, it is also a fundamental component in the definition of another unit of astronomical length, the parsec.

1212

Artist

An artist is a person engaged in an activity related to creating art, practicing the arts, or demonstrating an art. The common usage in both everyday speech and academic discourse is a practitioner in the visual arts only. The term is often used in the entertainment business, especially in a business context, for musicians and other performers (less often for actors). "Artiste" (the French for artist) is a variant used in English only in this context. Use of the term to describe writers, for example, is valid, but less common, and mostly restricted to contexts like criticism.

1213

Actaeon

Actaeon ( ; Ancient Greek: Ἀκταίων "Aktaion"), in Greek mythology, son of the priestly herdsman Aristaeus and Autonoe in Boeotia, was a famous Theban hero. Like Achilles in a later generation, he was trained by the centaur Chiron.

1214

Anglicanism

Anglicanism is a Western Christian tradition that evolved out of the practices, liturgy and identity of the Church of England following the Protestant Reformation in the 16th century. The word "Anglican" itself has its background in "ecclesia anglicana", a medieval Latin phrase dating to the 12th century or earlier, which means the "English Church".

1216

Athens

Athens ( ; Modern Greek: Αθήνα , "Athína" ] , Ancient Greek: Ἀθῆναι, "Athênai" , "Athínai") is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, with its recorded history spanning over 3,400 years and its earliest human presence starting somewhere between the 11th and 7th millennium BC.

1217

Anguilla

Anguilla ( ) is a British overseas territory in the Caribbean. It is one of the most northerly of the Leeward Islands in the Lesser Antilles, lying east of Puerto Rico and the Virgin Islands and directly north of Saint Martin. The territory consists of the main island of Anguilla, approximately 16 miles (26 km) long by 3 miles (5 km) wide at its widest point, together with a number of much smaller islands and cays with no permanent population. The island's capital is The Valley. The total land area of the territory is 35 square miles (90 km), with a population of approximately ( estimate).

1223

Telecommunications in Anguilla

This article is about communications systems in Anguilla.

1227

Ashmore and Cartier Islands

The Territory of Ashmore and Cartier Islands is an uninhabited external territory of Australia consisting of four low-lying tropical islands in two separate reefs, and the 12 nautical mile territorial sea generated by the islands. The territory is located in the Indian Ocean situated on the edge of the continental shelf, about 320 km off the northwest coast of Australia and 144 km south of the Indonesian island of Rote.

1234

Acoustic theory

Acoustic theory is a scientific field that relates to the description of sound waves. It derives from fluid dynamics. See acoustics for the engineering approach.

1235

Alexander Mackenzie (politician)

Alexander Mackenzie, PC (January 28, 1822April 17, 1892), was a Canadian politician who served as the second Prime Minister of Canada, in office from 1873 to 1878.

1239

Ashoka

Ashoka ( ; IAST: "Aśoka " ; died 232 BCE) was an Indian emperor of the Maurya Dynasty, who ruled almost all of the Indian subcontinent from  268 to 232 BCE. He was the grandson of the founder of the Maurya Dynasty, Chandragupta Maurya, who had created one of the largest empires in ancient India and then, according to Jain sources, renounced it all to become a Jain monk. One of India's greatest emperors, Ashoka expanded Chandragupta's empire, and reigned over a realm that stretched from present-day Afghanistan in the west to Bangladesh in the east. It covered the entire Indian subcontinent except for parts of present-day Tamil Nadu, Karnataka and Kerala. The empire's capital was Pataliputra (in Magadha, present-day Patna), with provincial capitals at Taxila and Ujjain.

1241

American (word)

The meaning of the word American in the English language varies according to the historical, geographical, and political context in which it is used. "American" is derived from "America", a term originally denoting all of the New World (also called "the Americas"). In some expressions, it retains this Pan-American sense, but its usage has evolved over time and, for various historical reasons, the word came to denote people or things specifically from the United States of America.

1242

Ada (programming language)

Ada is a structured, statically typed, imperative, wide-spectrum, and object-oriented high-level computer programming language, extended from Pascal and other languages. It has built-in language support for design-by-contract, extremely strong typing, explicit concurrency, offering tasks, synchronous message passing, protected objects, and non-determinism. Ada improves code safety and maintainability by using the compiler to find errors in favor of runtime errors. Ada is an international standard; the current version (known as Ada 2012) is defined by ISO/IEC 8652:2012.

1247

Alfonso Cuarón

Alfonso Cuarón Orozco (] ; born November 28, 1961) is a Mexican film director, screenwriter, producer, and editor best known for his dramas "A Little Princess" (1995) and

1252

Arianism

In Christianity, Arianism is a Christological concept which asserts the belief that Jesus Christ is the Son of God who was begotten by God the Father at a point in time, is distinct from the Father and is therefore subordinate to the Father. Arian teachings were first attributed to Arius (c. AD 256–336), a Christian presbyter in Alexandria, Egypt. The teachings of Arius and his supporters were opposed to the theological views held by Homoousian Christians, regarding the nature of the Trinity and the nature of Christ. The Arian concept of Christ is based on the belief that the Son of God did not always exist but was begotten by God the Father.

1254

August 1

August 1 is the day of the year in the Gregorian calendar.

1256

Antoninus Pius

Antoninus Pius (Latin: "Titus Aelius Hadrianus Antoninus Augustus Pius" ; 19 September 867 March 161), also known as Antoninus, was Roman emperor from 138 to 161. He was one of the Five Good Emperors in the Nerva–Antonine dynasty and the Aurelii.

1259

August 3

August 3 is the day of the year in the Gregorian calendar.

1260

Advanced Encryption Standard

The Advanced Encryption Standard (AES), also known by its original name Rijndael (] ), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001.

1261

April 26

April 26 is the day of the year in the Gregorian calendar.

1262

Argot

An argot ( ; from French "argot" 'slang') is a secret language used by various groups—e.g., schoolmates, outlaws, colleagues, among many others—to prevent outsiders from understanding their conversations. The term "argot" is also used to refer to the informal specialized vocabulary from a particular field of study, occupation, or hobby, in which sense it overlaps with jargon.

1264

Anisotropy

Anisotropy , is the property of being directionally dependent, which implies different properties in different directions, as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physical or mechanical properties (absorbance, refractive index, conductivity, tensile strength, etc.) An example of anisotropy is the light coming through a polarizer. Another is wood, which is easier to split along its grain than against it.

1267

Alpha decay

Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into an atom with a mass number that is reduced by four and an atomic number that is reduced by two. An alpha particle is identical to the nucleus of a helium-4 atom, which consists of two protons and two neutrons. It has a charge of +2e and a mass of 4u. For example, uranium-238 decays to form thorium-234. Alpha particles have a charge +2, but as a nuclear equation describes a nuclear reaction without considering the electrons – a convention that does not imply that the nuclei necessarily occur in neutral atoms – the charge is not usually shown.

1270

Extreme poverty

Extreme poverty, absolute poverty, destitution, or penury, was originally defined by the United Nations in 1995 as "a condition characterized by severe deprivation of basic human needs, including food, safe drinking water, sanitation facilities, health, shelter, education and information. It depends not only on income but also on access to services." In 2008, "extreme poverty" widely refers to earning below the international poverty line of $1.25/day (in 2005 prices), set by the World Bank. This measure is the equivalent to earning $1.00 a day in 1996 US prices, hence the widely used expression, living on "less than a dollar a day." The vast majority of those in extreme poverty – 96% – reside in South Asia, Sub-Saharan Africa, The West Indies, East Asia and the Pacific; nearly half live in India and China alone.

1271

Analytical Engine

The Analytical Engine was a proposed mechanical general-purpose computer designed by English mathematician and computer pioneer Charles Babbage. It was first described in 1837 as the successor to Babbage's difference engine, a design for a mechanical computer. The Analytical Engine incorporated an arithmetic logic unit, control flow in the form of conditional branching and loops, and integrated memory, making it the first design for a general-purpose computer that could be described in modern terms as Turing-complete. In other words, the logical structure of the Analytical Engine was essentially the same as that which has dominated computer design in the electronic era.

1273

Augustus

Augustus (Latin: "Imperātor Caesar Dīvī Fīlius Augustus" ; 23 September 63 BC – 19 August 14 AD) was the founder of the Roman Principate and considered the first Roman emperor, controlling the Roman Empire from 27 BC until his death in AD 14. He was born Gaius Octavius into an old and wealthy equestrian branch of the plebeian "gens" Octavia. His maternal great-uncle Julius Caesar was assassinated in 44 BC, and Octavius was named in Caesar's will as his adopted son and heir, then known as Octavianus (Anglicized as Octavian). He, Mark Antony, and Marcus Lepidus formed the Second Triumvirate to defeat the assassins of Caesar. Following their victory at the Battle of Philippi, the Triumvirate divided the Roman Republic among themselves and ruled as military dictators. The Triumvirate was eventually torn apart by the competing ambitions of its members. Lepidus was driven into exile and stripped of his position, and Antony committed suicide following his defeat at the Battle of Actium by Octavian in 31 BC.

1274

Geography of Antarctica

The geography of Antarctica is dominated by its south polar location and, thus, by ice. The Antarctic continent, located in the Earth's southern hemisphere, is centered asymmetrically around the South Pole and largely south of the Antarctic Circle. It is washed by the Southern (or Antarctic) Ocean or, depending on definition, the southern Pacific, Atlantic, and Indian Oceans. It has an area of more than 14 million km².

1279

Transport in Antarctica

Transport in Antarctica has transformed from explorers crossing the isolated remote area of Antarctica by foot to a more open area due to human technologies enabling more convenient and faster transport, predominantly by air and water, as well as land.

1285

Geography of Alabama

This article will go through a wide range of topics of the geography of the state of Alabama. It is 30th in size and borders four U.S. states: Mississippi, Tennessee, Georgia, and Florida. It also borders the Gulf of Mexico.

1286

List of Governors of Alabama

The Governor of Alabama is the chief executive of the U.S. state of Alabama. The governor is the head of the executive branch of Alabama's state government and is charged with enforcing state laws. The governor has the power to either approve or veto bills passed by the Alabama Legislature, to convene the legislature, and to grant pardons, except in cases of impeachment. The governor is also the commander-in-chief of the state's military forces.

1288

Apocrypha

Apocrypha are works, usually written, of unknown authorship or of doubtful origin. Biblical apocrypha is a set of texts included in the Latin Vulgate and Septuagint but not in the Hebrew Bible. While Catholic tradition considers the texts to be deuterocanonical, Protestants consider them apocryphal. Thus, Protestant bibles do not include the books within the Old Testament but have often included them in a separate section. Other non-canonical apocryphal texts are generally called pseudepigrapha, a term that means "false writings".

1291

Antarctic Treaty System

The Antarctic Treaty and related agreements, collectively known as the Antarctic Treaty System (ATS), regulate international relations with respect to Antarctica, Earth's only continent without a native human population. For the purposes of the treaty system, Antarctica is defined as all of the land and ice shelves south of 60°S latitude. The treaty, entering into force in 1961 and having 53 parties as of 2016, sets aside Antarctica as a scientific preserve, establishes freedom of scientific investigation and bans military activity on that continent. The treaty was the first arms control agreement established during the Cold War. The Antarctic Treaty Secretariat headquarters have been located in Buenos Aires, Argentina, since September 2004.

1293

Alfred Lawson

Alfred William Lawson (March 24, 1869 – November 29, 1954) was a professional baseball player, manager, and league promoter from 1887 through 1916 and went on to play a pioneering role in the U.S. aircraft industry. He published two early aviation trade journals.

1298

Ames, Iowa

Ames is a city located in the central part of Story County, Iowa, United States. It is located approximately 30 mi north of Des Moines, and had a 2010 population of 58,965. The U.S. Census Bureau designates the Ames metropolitan statistical area as encompassing all of Story County; combined with the Boone, Iowa micropolitan statistical area (Boone County, Iowa), the pair make up the larger Ames-Boone combined statistical area. While Ames is the largest city in Story County, the county seat is in the nearby city of Nevada 8 mi east of Ames.

1300

Abalone

Abalone ( or ; via Spanish "abulón ", from the Rumsen language "aulón") is a common name for any of a group of small to very large sea snails, marine gastropod molluscs in the family Haliotidae.

1301

Abbess

In Christianity, an abbess (Latin "abbatissa", feminine form of "abbas," abbot) is the female superior of a community of nuns, which is often an abbey.

1303

Abdominal surgery

The term abdominal surgery broadly covers surgical procedures that involve opening the abdomen. Surgery of each abdominal organ is dealt with separately in connection with the description of that organ (see stomach, kidney, liver, etc.) Diseases affecting the abdominal cavity are dealt with generally under their own names (e.g. appendicitis).

1305

Abensberg

Abensberg (] ) is a town in the Lower Bavarian district of Kelheim, in Bavaria, Germany, lying around 30 km southwest of Regensburg, 40 km east of Ingolstadt, 50 northwest of Landshut and 100 km north of Munich. It is situated on the Abens river, a tributary of the Danube.

1306

Arminianism

Arminianism is based on theological ideas of the Dutch Reformed theologian Jacobus Arminius (1560–1609) and his historic supporters known as Remonstrants. His teachings held to the five solae of the Reformation, but they were distinct from particular teachings of Martin Luther, Huldrych Zwingli, John Calvin, and other Protestant Reformers. Jacobus Arminius (Jakob Harmenszoon) was a student of Theodore Beza (Calvin's successor) at the Theological University of Geneva. Arminianism is known to some as a soteriological diversification of Protestant Calvinist Christianity. However, to others, Arminianism is a reclamation of early Church theological consensus.

1307

The Alan Parsons Project

The Alan Parsons Project was the collective reference to several lineups of a British progressive rock team, active between 1975 and 1990, whose rosters consisted of Alan Parsons and Eric Woolfson surrounded by a varying number of session musicians and some relatively consistent band members such as guitarist Ian Bairnson, arranger Andrew Powell, bassist and vocalist David Paton, drummer Stuart Elliott, and vocalist Lenny Zakatek.

1309

Almost all

In mathematics, the phrase "almost all" has a number of specialised uses which extend its intuitive meaning.

1313

Aromatic hydrocarbon

An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle. In contrast, aliphatic hydrocarbons lack this delocalization. The term 'aromatic' was assigned before the physical mechanism determining aromaticity was discovered; the term was coined as such simply because many of the compounds have a sweet or pleasant odour. The configuration of six carbon atoms in aromatic compounds is known as a benzene ring, after the simplest possible such hydrocarbon, benzene. Aromatic hydrocarbons can be "monocyclic" (MAH) or "polycyclic" (PAH).

1315

Abbey

An abbey is a complex of buildings used by members of a religious order under the governance of an abbot or abbess. It provides a place for religious activities, work and housing of Christian monks and nuns. The concept of the abbey has developed over many centuries from the early monastic ways of religious men and women where they would live isolated from the lay community about them. Religious life in an abbey may be monastic. An abbey may be the home of an enclosed religious order or may be open to visitors. The layout of the church and associated buildings of an abbey often follows a set plan determined by the founding religious order. Abbeys are often self-sufficient while using any abundance of produce or skill to provide care to the poor and needy, refuge to the persecuted or education to the young. Some abbeys offer accommodation to people who are seeking spiritual retreat. There are many famous abbeys across Europe.

1316

Annales School

The "Annales" School (] ) is a group of historians associated with a style of historiography developed by French historians in the 20th century to stress long-term social history. It is named after its scholarly journal "Annales d'histoire économique et sociale", which remains the main source of scholarship, along with many books and monographs. The school has been highly influential in setting the agenda for historiography in France and numerous other countries, especially regarding the use of social scientific methods by historians, emphasizing social rather than political or diplomatic themes, and for being generally hostile to the class analysis of Marxist historiography.

1317

Antimatter

In modern physics, antimatter is defined as a material composed of the antiparticle (or "partners") to the corresponding particles of ordinary matter.

1322

Casa Batlló

Casa Batlló (] ) is a renowned building located in the center of Barcelona and is one of Antoni Gaudí’s masterpieces. A remodel of a previously built house, it was redesigned in 1904 by Gaudí and has been refurbished several times after that. Gaudí's assistants Domènec Sugrañes i Gras, Josep Canaleta and Joan Rubió also contributed to the renovation project. The local name for the building is "Casa dels ossos" (House of Bones), as it has a visceral, skeletal organic quality.

1324

Park Güell

The Park Güell (Catalan: "Parc Güell" ] ) is a public park system composed of gardens and architectonic elements located on Carmel Hill, in Barcelona, Catalonia (Spain). Carmel Hill belongs to the mountain range of Collserola – the Parc del Carmel is located on the northern face. Park Güell is located in La Salut, a neighborhood in the Gràcia district of Barcelona. With urbanization in mind, Eusebi Güell assigned the design of the park to Antoni Gaudí, a renowned architect and the face of Catalan modernism. The park was built between 1900 and 1914 and was officially opened as a public park in 1926. In 1984, UNESCO declared the park a World Heritage Site under "Works of Antoni Gaudí".

1325

Casa Milà

Casa Milà (] , ] ), popularly known as "La Pedrera" or "open quarry", a reference to its unconventional rough-hewn appearance, is a modernist building in Barcelona, Catalonia, Spain. It was the last private residence designed by architect Antoni Gaudí and was built between 1906 and 1910.

1327

Antiparticle

In particle physics, corresponding to most kinds of particles there is an associated antiparticle with the same mass and opposite charge (including electric charge). For example, the antiparticle of the electron is the positron (antielectron), which has positive charge and is produced naturally in certain types of radioactive decay. The opposite is also true: the antiparticle of the positron is the electron.

1331

Arabian Prince

Kim Renard Nazel (born June 17, 1965), better known by the stage name Arabian Prince, is an American rapper, singer-songwriter, record producer and DJ.

1332

August 7

August 7 is the day of the year in the Gregorian calendar.

1333

August 8

August 8 is the day of the year in the Gregorian calendar.

1334

April 16

April 16 is the day of the year in the Gregorian calendar.

1335

Associative property

In mathematics, the associative property is a property of some binary operations. In propositional logic, associativity is a valid rule of replacement for expressions in logical proofs.

1336

Apache Software Foundation

The Apache Software Foundation (ASF) is an American non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. The ASF was formed from the Apache Group and incorporated in Delaware, U.S., in June 1999.

1338

Americans with Disabilities Act of 1990

The Americans with Disabilities Act of 1990 ( /12101 § 12101 ) is a civil rights law that prohibits discrimination based on disability. It affords similar protections against discrimination to Americans with disabilities as the Civil Rights Act of 1964, which made discrimination based on race, religion, sex, national origin, and other characteristics illegal. In addition, unlike the Civil Rights Act, the ADA also requires covered employers to provide reasonable accommodations to employees with disabilities, and imposes accessibility requirements on public accommodations.

1344

Apple I

Apple Computer 1, also known later as the Apple I, or Apple-1, is a desktop computer released by the Apple Computer Company (now Apple Inc.) in 1976. It was designed and hand-built by Steve Wozniak. Wozniak's friend Steve Jobs had the idea of selling the computer. The Apple I was Apple's first product, and to finance its creation, Jobs sold his only motorized means of transportation, a VW Microbus, for a few hundred dollars, and Wozniak sold his HP-65 calculator for $500; however, Wozniak said that Jobs planned to use his bicycle if necessary. It was demonstrated in July 1976 at the Homebrew Computer Club in Palo Alto, California.

1346

Apatosaurus

Apatosaurus ( ; meaning "deceptive lizard") is a genus of extinct sauropod dinosaurs that lived in North America during the Late Jurassic period. Othniel Charles Marsh described and named the first-known species, A. ajax, in 1877, and a second species, A. louisae, was discovered and named by William H. Holland in 1916. "Apatosaurus" lived about 152 to 151 million years ago (mya), during the early Tithonian age, and are now known from fossils in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, and Utah in the United States. "Apatosaurus" had an average length of 21 - , and an average mass of 16.4 - . A few specimens indicate a maximum length of 11–30% greater than average and a mass of 32.7 - .

1347

Allosaurus

Allosaurus ( ) is a genus of large theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period (Kimmeridgian to early Tithonian). The name ""Allosaurus"" means "different lizard". It is derived from the Greek ἄλλος /"allos" ("different, other") and σαῦρος /"sauros" ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. These remains became known as "Antrodemus". As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Indeed, it has been a top feature in several films and documentaries about prehistoric life.

1348

AK-47

The AK-47, or AK as it is officially known (Russian: Автомат Калашникова , "Avtomat Kalashnikova ", 'Kalashnikov's Automatic Rifle' ), also known as the Kalashnikov, is a selective-fire (semi-automatic and fully automatic), gas-operated 7.62×39mm assault rifle, developed in the Soviet Union by Mikhail Kalashnikov. It is the originating firearm of the Kalashnikov rifle (or "AK") family.

1349

Atanasoff–Berry computer

The Atanasoff–Berry computer (ABC) was the first automatic electronic digital computer, an early electronic digital computing device that has remained somewhat obscure. The ABC's priority is debated among historians of computer technology, because it was neither programmable, nor Turing-complete.

1354

Andes

The Andes or Andean Mountains (Spanish: "Cordillera de los Andes" ) are the longest continental mountain range in the world. They form a continuous highland along the western edge of South America. This range is about 7000 km long, about 200 to wide (widest between 18° south and 20° south latitude), and of an average height of about 4000 m . The Andes extend from north to south through seven South American countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Argentina and Chile.

1356

Ancylopoda

Ancylopoda is a group of browsing, herbivorous, mammals in the Perissodactyla that show long, curved and cleft claws. Morphological evidence indicates the Ancylopoda diverged from the tapirs, rhinoceroses and horses (Euperissodactyla) after the Brontotheria, however earlier authorities such as Osborn sometimes considered the Ancylopoda to be outside Perissodactyla or, as was popular more recently, to be related to Brontotheria.

1358

Anchor

An anchor is a device, normally made of metal, used to connect a vessel to the bed of a body of water to prevent the craft from drifting due to wind or current. The word derives from Latin "ancora", which itself comes from the Greek ἄγκυρα ("ankura").

1359

Anbar (town)

Anbar (Arabic: الأنبار‎ ‎ ) was a town in Iraq, at lat. 33 deg. 22' N., long. 43 deg. 49' E, on the east bank of the Euphrates, just south of the Nahr 'Isa, or Sakhlawieh canal, the northernmost of the canals connecting that river with the Tigris.

1360

Anazarbus

Anazarbus (Ancient Greek: Ἀναζαρβός , medieval Ain Zarba; modern Anavarza; Arabic: عَيْنُ زَرْبَة‎ ‎ ) was an ancient Cilician city and (arch)bishopric, which remains a Latin Catholic titular see.

1361

Anagram

An anagram is word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. For example, the word "anagram" can be rearranged into "nag a ram".

1362

Anadyr River

Anadyr (Russian: Ана́дырь ) is a river in the far northeast Siberia which flows into Anadyr Bay of the Bering Sea and drains much of the interior of Chukotka Autonomous Okrug. Its basin corresponds to the Anadyrsky District of Chukotka.

1363

André-Marie Ampère

André-Marie Ampère ( ; ] ; 20 January 177510 June 1836) was a French physicist and mathematician who was one of the founders of the science of classical electromagnetism, which he referred to as "electrodynamics". He is also the inventor of numerous applications, such as the solenoid (a term coined by him) and the electrical telegraph. An autodidact, Ampère was a member of the "Académie des sciences" and professor at the "École polytechnique" and the "Collège de France".

1365

Ammonia

Ammonia or azane is a compound of nitrogen and hydrogen with the formula NH. The simplest pnictogen hydride, ammonia is a colourless gas with a characteristic pungent smell. It contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products.

1366

Amethyst

Amethyst is a violet variety of quartz often used in jewelry.

1367

Albertosaurus

Albertosaurus ( ; meaning "Alberta lizard") is a genus of tyrannosaurid theropod dinosaurs that lived in western North America during the Late Cretaceous Period, about 70 million years ago. The type species, "A. sarcophagus", was apparently restricted in range to the modern-day Canadian province of Alberta, after which the genus is named. Scientists disagree on the content of the genus, with some recognizing "Gorgosaurus libratus" as a second species.

1368

Assembly language

An assembly (or assembler) language, often abbreviated asm, is a low-level programming language for a computer, or other programmable device, in which there is a very strong (but often not one-to-one) correspondence between the language and the architecture's machine code instructions. Each assembly language is specific to a particular computer architecture. In contrast, most high-level programming languages are generally portable across multiple architectures but require interpreting or compiling. Assembly language may also be called "symbolic machine code".

1369

Ambrosia

In the ancient Greek myths, ambrosia ( , Greek: ἀμβροσία, "immortality" ) is sometimes the food or drink of the Greek gods, often depicted as conferring longevity or immortality upon whoever consumed it. It was brought to the gods in Olympus by doves.

1370

Ambrose

Aurelius Ambrosius (Italian: "Sant'Ambrogio" ] ; Lombard: Sant'Ambroeus ] ), better known in English as Saint Ambrose ( ;  340 4 April 397), was a bishop of Milan who became one of the most influential ecclesiastical figures of the 4th century. He was the Roman governor of Liguria and Emilia, headquartered in Milan, before being made bishop of Milan by popular acclamation in 374. Ambrose was a staunch opponent of Arianism, and has been accused of fostering persecutions of Arians, Jews, and pagans.

1371

Ambracia

Ambracia ( ; Greek: Ἀμβρακία , occasionally Ἀμπρακία , "Ampracia"), was a city of ancient Greece on the site of modern Arta. It was founded as a Corinthian colony in the 7th century BC and was situated about 7 miles from the Ambracian Gulf, on a bend of the navigable river Arachthos (or Aratthus), in the midst of a fertile wooded plain.

1372

Amber

Amber is fossilized tree resin, which has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects. Amber is used in jewelry. It has also been used as a healing agent in folk medicine.

1373

Amalaric

Amalaric (Gothic: Amalareiks), or in Spanish and Portuguese, "Amalarico", (502–531) was king of the Visigoths from 511 until his death in battle in 531. He was a son of king Alaric II and his first wife Theodegotha, daughter of Theoderic the Great King of the Ostrogoths.

1374

Alphorn

The alphorn or alpenhorn or alpine horn is a labrophone, consisting of a wooden natural horn of conical bore, having a wooden cup-shaped mouthpiece, used by mountain dwellers in the Swiss Alps, Austrian Alps, Bavarian Alps in Germany, French Alps, and elsewhere. Similar wooden horns were used for communication in most mountainous regions of Europe, from the Alps to the Carpathians.

1376

Army

An army (from Latin "arma" "arms, weapons" via Old French "armée", "armed" (feminine)) or ground force is a fighting force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or state. It may also include other branches of the military such as the air force via means of aviation corps. Within a national military force, the word army may also mean a field army. They differ from army reserves who are activated only during such times as war or natural disasters.

1380

Alligatoridae

The family Alligatoridae of crocodylians includes alligators and caimans.

1383

Alder

Alder is the common name of a genus of flowering plants (Alnus) belonging to the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes.

1384

Amos Bronson Alcott

Amos Bronson Alcott ( ; November 29, 1799March 4, 1888) was an American teacher, writer, philosopher, and reformer. As an educator, Alcott pioneered new ways of interacting with young students, focusing on a conversational style, and avoided traditional punishment. He hoped to perfect the human spirit and, to that end, advocated a vegan diet before the term was coined. He was also an abolitionist and an advocate for women's rights.

1386

Arachnophobia

Arachnophobia is a specific phobia: the fear of spiders and other arachnids such as scorpions.

1387

Alabaster

Alabaster is a mineral or rock that is soft and often used for carving, as well as being processed for plaster powder. The term is used in different ways by archaeologists and the stone processing industry on the one hand, and geologists on the other. The first use is in a wider meaning, covering varieties of two different minerals: the fine-grained massive type of gypsum, as well as the fine-grained banded type of calcite. Geologists only define the gypsum variety as alabaster. Chemically, gypsum is a hydrous sulfate of calcium, while calcite is a carbonate of calcium.

1389

Ahab

Ahab (; Akkadian: "Aḫabbu" ; Greek: Αχααβ ; Latin: "Achab" ) was the seventh king of Israel since Jeroboam I, the son and successor of Omri, and the husband of Jezebel of Sidon, according to the Hebrew Scriptures. The Hebrew Bible presents Ahab as a wicked king. He is criticised for following the ways of his wife Jezebel, killing his subject Naboth, and leading the nation of Israel into idolatry.

1391

ASIC (disambiguation)

ASIC is an integrated circuit developed for a particular use, as opposed to a general-purpose device.

1392

Dasyproctidae

Dasyproctidae is a family of large South American rodents, comprising the agoutis and acouchis. Their fur is a reddish or dark colour above, with a paler underside. They are herbivorous, often feeding on ripe fruit that falls from trees. They live in burrows, and, like squirrels, will bury some of their food for later use.

1394

Algol

Algol, designated Beta Persei (β Persei, abbreviated Beta Per, β Per), known colloquially as the Demon Star, is a bright multiple star in the constellation of Perseus. It is the first and best known eclipsing binary, and one of the first non-nova variable stars to be discovered. It is a three-star system, consisting of Beta Persei Aa1, Aa2, and Ab - in which the large and bright primary β Persei Aa1 is regularly eclipsed by the dimmer β Persei Aa2. Thus, Algol's magnitude is usually near-constant at 2.1, but regularly dips to 3.4 every 2.86 days (2 days, 20 hours and 49 minutes) during the roughly 10-hour-long partial eclipses. There is also a secondary eclipse (the "second minimum") when the brighter star occults the fainter secondary. This secondary eclipse can only be detected photoelectrically.

1395

Amazing Grace

"Amazing Grace" is a Christian hymn published in 1779, with words written by the English poet and Anglican clergyman John Newton (1725–1807).

1397

AOL

AOL (formerly a company known as AOL Inc., originally known as America Online, and stylized as Aol) is a web portal and online service provider based in New York. It is a brand marketed by Oath, a subsidiary of Verizon Communications. AOL was one of the early pioneers of the Internet in the mid-1990s, and the most recognized brand on the web in the U.S. It originally provided a dial-up service to millions of Americans, as well as providing a web portal, e-mail, instant messaging and later a web browser following its purchase of Netscape. At the height of its popularity, it purchased the media conglomerate Time Warner in the largest merger in U.S. history. AOL rapidly declined thereafter, partly due to the decline of dial-up to broadband. AOL was eventually spun off from Time Warner in 2009, with Tim Armstrong appointed the new CEO. Under his leadership, the company invested in media brands and advertising technologies.

1400

Anno Domini

The terms anno Domini (AD) and before Christ (BC) are used to label or number years in the Julian and Gregorian calendars. The term "anno Domini " is Medieval Latin and means "in the year of the Lord", but is often translated as "in the year of our Lord".

1408

Alcuin

Alcuin of York ( ; Latin: "Flaccus Albinus Alcuinus" ; 735 – 19 May 804 AD)—also called Ealhwine, Alhwin or Alchoin—was an English scholar, clergy, poet and teacher from York, Northumbria. He was born around 735 and became the student of Archbishop Ecgbert at York. At the invitation of Charlemagne, he became a leading scholar and teacher at the Carolingian court, where he remained a figure in the 780s and '90s.

1409

Angilbert

Saint Angilbert ( – 18 February 814), sometimes known as Angilberk or Engelbert, was a noble Frankish poet who was educated under Alcuin and served Charlemagne as a secretary, diplomat, and son-in-law. He was venerated as a pre-Congregation saint and is still honored on the day of his death, 18 February.

1412

Amine

In organic chemistry, amines ( , ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; see for a list of amines. Inorganic derivatives of ammonia are also called amines, such as chloramine (NClH); see .

1416

April 29

April 29 is the day of the year in the Gregorian calendar.

1417

August 14

August 14 is the day of the year in the Gregorian calendar.