asteroid
A naturally occurring solid object, which is smaller than a planet and a dwarf planet, larger than a meteoroid and not a comet, that orbits a star and often has an irregular shape.
In the Solar system, such a body that orbits within the orbit of Jupiter

asteroidean
Any starfish of the class Asteroidea

asteroideans
plural of asteroidean

asteroidians
plural of asteroidian

asteroids
plural of asteroid

asterophryine
Any of the subfamily Asterophryinae of microhylid frogs.

asterophryines
plural of asterophryine

asteropygid
Synonym of asteropyginid.

asteropyginid
Any trilobite of the genus †Asteropyge.

asterozoa
plural of asterozoan

asterozoan
Any animal in the echinoderm subphylum Asterozoa, which includes the brittle stars, basket stars and starfish

asterozoans
plural of asterozoan

astigmatid
Any mite of the clade Astigmatina

astigmatids
plural of astigmatid

astragaloi
plural of astragalos

astragalos
An ancient form of die (used in games of chance) made from the knucklebone of a sheep.

astrapotherian
Any member of the order †Astrapotheria of extinct mammals.

astrapotherians
plural of astrapotherian

astrapotheriid
Any of the extinct mammals in the family Astrapotheriidae.

astrapotheriids
plural of astrapotheriid

astrochimp
A chimpanzee used in a spaceflight program.

astrochimps
plural of astrochimp

astrocoeniid
Any of the stony corals in the family Astrocoeniidae.

astrocoeniids
plural of astrocoeniid

astronaut
A member of the crew of a spaceship or other spacecraft that travels beyond Earth's atmosphere, or someone trained to serve that purpose.
A member of the crew of a spaceship or other spacecraft that travels beyond Earth's atmosphere, or someone trained to serve that purpose.
A person (typically man) working abroad away from their family.

astronauts
plural of astronaut

astronesthes
Synonym of astronesthid.

astrophorid
Any member of the order Astrophorida of marine demosponges.

astrophorids
plural of astrophorid

astrozoology
The branch of xenology dealing with extraterrestrial animals.

asuang
Alternative form of aswang.

asuangs
plural of asuang

aswail
The sloth bear (Melursus ursinus), an India bear.

aswang
A shapeshifting evil creature in Philippine mythology

aswangs
plural of aswang

asymmetron
A massive scalar field proposed as a form of dark matter

asymmetrons
plural of asymmetron

atavism
The reappearance of an ancestral characteristic in an organism after several generations of absence; a throwback.
The recurrence or reversion to a past behaviour, method, characteristic or style after a long period of absence.
Reversion to past primitive behavior, especially violence.

atavisms
plural of atavism

atelestid
Any of the flies in the family Atelestidae.

atelestids
plural of atelestid

atelid
Any monkey in the family Atelidae.

atelids
plural of atelid

ateline
Any monkey of the subfamily Atelinae

atelines
plural of ateline

ateuchosaurid
Any skink of the genus Ateuchosaurus

ateuchosaurids
plural of ateuchosaurid

atherine
A small marine fish of the family Atherinidae having a silvery stripe along the sides.

atherines
plural of atherine

atherosclerogeneses
plural of atherosclerogenesis

atherosclerogenesis
The generation of atherosclerosis.

athoracophorid
Any slug in the family Athoracophoridae.

athoracophorids
plural of athoracophorid

atlantes
plural of atlas

atlantogenatan
Any mammal of the clade Atlantogenata.

atlantogenatans
plural of atlantogenatan

atlantosaurid
Any dinosaur in the family Atlantosauridae, which is probably a synonym of the Diplodocidae.

atlantosaurids
plural of atlantosaurid

atlas
A bound collection of maps often including tables, illustrations or other text.
A bound collection of tables, illustrations, etc. on any given subject.
A detailed visual conspectus of something of great and multi-faceted complexity, with its elements splayed so as to be presented in as discrete a manner as possible whilst retaining a realistic view of the whole.
A family of coordinate charts that cover a manifold.
The uppermost vertebra of the cervical spine in the neck in humans and some other animals.
One who supports a heavy burden; mainstay.
A figure of a man used as a column.
A sheet of paper measuring 26 inches by 34 inches.
An image or texture containing a number of other images or textures, so as to reduce the cost of loading them separately.

atlases
plural of atlas

atlasses
plural of atlas

atoke
An atokous organism.

atokes
plural of atoke

atoposaurid
Any of the extinct reptiles in the family Atoposauridae.

atoposaurids
plural of atoposaurid

atrichornithid
Any member of the Atrichornithidae.

atrichornithids
plural of atrichornithid

atrocha
An annelid larva in the stage where no circles of cilia are developed.

atrochae
plural of atrocha

atrophia
Archaic form of atrophy.

atrophias
plural of atrophia

attagen
A grey partridge (Perdix perdix) of Eurasia.
A Pallas's sandgrouse (Syrrhaptes paradoxus) of Central Asia and occurring as a vagrant in Europe.

attagens
plural of attagen

attamole
Alternative form of attomole.

attamoles
plural of attamole

attelabid
Any member of the family Attelabidae of weevils.

attelabids
plural of attelabid

attercop
A spider.
A peevish or ill-natured person.

attercops
plural of attercop

attercrop
Alternative form of attercop (“a spider”).

attercrops
plural of attercrop

attestation
A thing that serves to bear witness, confirm, or authenticate; validation, verification, documentation.
A confirmation or authentication.
The process, performed by accountants or auditors, of providing independent opinion on published financial and other business records of an enterprise, public agency, or other organization.
An appearance in print or otherwise recorded on a permanent medium.

attestations
plural of attestation

attid
Any of the family Attidae of jumping spiders, now considered part of the Salticidae.

attids
plural of attid

attomole
10⁻¹⁸ of a mole. This is only about 600,000 particles.

attomoles
plural of attomole

attractant
Anything that attracts, but especially a substance (such as a pheromone) that attracts insects or other animals

attractants
plural of attractant

atyid
Any member of the family Atyidae of freshwater shrimp.

atyids
plural of atyid

atypid
Any member of the Atypidae.

atypids
plural of atypid

atypoid
Any mygalomorph spider of the clade Atypoidea

atypoids
plural of atypoid

auchenium
The back of a bird's neck; the nape.

auchenorrhynchan
Any cicada or similar insect of the suborder Auchenorrhyncha

auchenorrhynchans
plural of auchenorrhynchan

augaptilid
Any member of the family Augaptilidae of copepods.

augaptilids
plural of augaptilid

augerino
A giant mythical wormlike creature of the western US.

auguries
plural of augury

augury
A divination based on the appearance and behaviour of animals.
An omen or prediction; a foreboding; a prophecy.
An event that is experienced as indicating important things to come.

aulacid
Any member of the family Aulacidae of wasps.

aulacids
plural of aulacid

aulacopleurid
Any trilobite of the family Aulacopleuridae

aulacopleurids
plural of aulacopleurid

aulnager
Alternative form of alnager.

aulnagers
plural of aulnager

aulopiforms
plural of aulopiform

aulorhynchid
Any member of the family Aulorhynchidae of gasterosteiform fish.

aulorhynchids
plural of aulorhynchid

ausktribosphenid
Any member of the Ausktribosphenidae.

ausktribosphenids
plural of ausktribosphenid

australidelphian
Any marsupial of the superorder Australidelphia

australidelphians
plural of australidelphian

australobatrachian
Any frog of the suborder Australobatrachia

australobatrachians
plural of australobatrachian

autapomorph
An organism that possesses a derived trait that is unique to a particular taxon.

autapomorphs
plural of autapomorph

autecologies
plural of autecology

autecology
one of two broad subdivisions of ecology, which studies the individual organism or species.

autetaranga
The sand daphne