Consonant
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are and [b], pronounced with the lips; and [d], pronounced with the front of the tongue; and [g], pronounced with the back of the tongue; , pronounced in the throat; , [v], and , pronounced by forcing air through a narrow channel (fricatives); and and , which have air flowing through the nose (nasals). Contrasting with consonants are vowels. Since the number of speech sounds in the world's languages is much greater than the number of letters in any one  alphabet, linguists have devised systems such as the International Phonetic Alphabet (IPA) to assign a unique and unambiguous symbol to each attested consonant. The English alphabet has fewer consonant letters than the English language has consonant sounds, so digraphs like , , , and are used to extend the alphabet, though some letters and digraphs represent more than one consonant. For example, the sound spelled in "this" is a different consonant from the sound in "thin". (In the IPA, these are and , respectively.) Etymology. The word "consonant" comes from Latin oblique stem , from 'sounding-together', a calque of Greek (plural , ). Dionysius Thrax calls  consonants ( 'sounded with') because in Greek they can only be pronounced with a vowel. He divides them into two subcategories: ( 'half-sounded'), which are the continuants, and ( 'unsounded'), which correspond to plosives. This description does not apply to some languages, such as the Salishan languages, in which plosives may occur without vowels (see Nuxalk), and the modern concept of 'consonant' does not require co-occurrence with a vowel. Consonant "sounds" and consonant "letters". The word consonant may be used ambiguously for both speech sounds and the letters of the alphabet used to write them. In English, these letters are B , C, D, F, G, J, K, L, M, N, P, Q, S, T, V, X, Z and often H, R, W, Y. In English orthography, the letters H, R, W, Y and the digraph GH are used for both consonants and vowels. For instance, the letter Y stands for the consonant in yoke", the vowel in "myth", the vowel in "funny, the diphthong in "sky, and forms several digraphs for other diphthongs, such as "say, boy, key. Similarly, R commonly indicates or modifies a vowel in non-rhotic accents. This article is concerned with consonant sounds, however they are written . Consonants versus vowels. Consonants and vowels correspond to distinct parts of a syllable: The most sonorous part of the syllable (that is, the part that's easiest to sing), called the "syllabic peak" or "nucleus," is typically a vowel, while the less sonorous margins (called the "onset" and "coda") are typically consonants. Such syllables may be abbreviated CV, V, and CVC, where C stands for consonant and V stands for vowel. This can be argued to be the only pattern found in most of the world's languages, and perhaps the primary pattern in all of them. However, the distinction  between consonant and vowel is not always clear cut: there are syllabic consonants and non-syllabic vowels in many of the world's languages. One blurry area is in segments variously called "semivowels", "semiconsonants", or "glides". On one side, there are vowel-like segments that are not in themselves syllabic, but form diphthongs as part of the syllable nucleus, as the "i" in English "boil" . On the other, there are approximants that behave like consonants in forming onsets, but are articulated very much like vowels, as the "y" in English "yes" . Some phonologists model these as both being the underlying  vowel , so that the English word "bit" would phonemically be , "beet" would be , and "yield" would be phonemically . Likewise, "foot" would be , "food" would be , "wood" would be , and "wooed" would be . However, there is a (perhaps allophonic) difference in articulation between these segments, with the in "yes" and "yield" and the of "wooed" having more constriction and a more definite place of articulation than the in "boil" or "bit" or the of "foot". The other problematic area is that of syllabic consonants, segments articulated as consonants but occupying the nucleus of a syllable. This may be the case for  words such as "church" in rhotic dialects of English, although phoneticians differ in whether they consider this to be a syllabic consonant, , or a rhotic vowel, : Some distinguish an approximant that corresponds to a vowel , for "rural" as or ; others see these as a single phoneme, . Other languages use fricative and often trilled segments as syllabic nuclei, as in Czech and several languages in Democratic Republic of the Congo, and China, including Mandarin Chinese. In Mandarin, they are historically allophones of , and spelled that way in Pinyin. Ladefoged and Maddieson call these "fricative vowels" and say that "they can usually  be thought of as syllabic fricatives that are allophones of vowels". That is, phonetically they are consonants, but phonemically they behave as vowels. Many Slavic languages allow the trill and the lateral as syllabic nuclei (see Words without vowels). In languages like Nuxalk, it is difficult to know what the nucleus of a syllable is, or if all syllables even have nuclei. If the concept of 'syllable' applies in Nuxalk, there are syllabic consonants in words like (?) 'seal fat'. Miyako in Japan is similar, with 'to build' and 'to pull'. Features. Each spoken consonant can be distinguished by several phonetic  features: All English consonants can be classified by a combination of these features, such as "voiceless alveolar stop" . In this case, the airstream mechanism is omitted. Some pairs of consonants like "p::b", "t::d" are sometimes called fortis and lenis, but this is a phonological rather than phonetic distinction. Consonants are scheduled by their features in a number of IPA charts: Examples. The recently extinct Ubykh language had only 2 or 3 vowels but 84 consonants; the Taa language has 87 consonants under one analysis, 164 under another, plus some 30 vowels and tone. The types of consonants used in various  languages are by no means universal. For instance, nearly all Australian languages lack fricatives; a large percentage of the world's languages lack voiced stops such as , , as phonemes, though they may appear phonetically. Most languages, however, do include one or more fricatives, with being the most common, and a liquid consonant or two, with the most common. The approximant is also widespread, and virtually all languages have one or more nasals, though a very few, such as the Central dialect of Rotokas, lack even these. This last language has the smallest number of consonants in the world, with just  six. Most common. The most frequent consonants in rhotic American English (that is, the ones appearing most frequently during speech) are . ( is less common in non-rhotic accents.) The most frequent consonant in many other languages is . The most universal consonants around the world (that is, the ones appearing in nearly all languages) are the three voiceless stops , , , and the two nasals , . However, even these common five are not completely universal. Several languages in the vicinity of the Sahara Desert, including Arabic, lack . Several languages of North America, such as Mohawk, lack both of the labials and . The Wichita language  of Oklahoma and some West African languages, such as Ijo, lack the consonant on a phonemic level, but do use it phonetically, as an allophone of another consonant (of in the case of Ijo, and of in Wichita). A few languages on Bougainville Island and around Puget Sound, such as Makah, lack both of the nasals and altogether, except in special speech registers such as baby-talk. The 'click language' Nǁng lacks , and colloquial Samoan lacks both alveolars, and . Despite the 80-odd consonants of Ubykh, it lacks the plain velar in native words, as do the related Adyghe and  Kabardian languages. But with a few striking exceptions, such as Xavante and Tahitian—which have no dorsal consonants whatsoever—nearly all other languages have at least one velar consonant: most of the few languages that do not have a simple (that is, a sound that is generally pronounced ) have a consonant that is very similar. For instance, an areal feature of the Pacific Northwest coast is that historical *k has become palatalized in many languages, so that Saanich for example has and but no plain ; similarly, historical *k in the Northwest Caucasian languages became palatalized to in extinct Ubykh and  to in most Circassian dialects. Audio samples. The following pages include consonant charts with links to audio samples.