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The classification of speech sounds The English Consonants

Any speech sound characterized by an articulation in which a closure or narrowing of the vocal tract completely or partially blocks the flow of air has its specific name by classification and functioning. Consonants are usually classified according to the place of articulation (e.g. palate, teeth, lips); the manner of articulation, as in stops (complete closure of the oral passage, released with a burst of air), fricatives (forcing of breath through a constricted passage), and trills (vibration of the tip of the tongue or the uvula); and the presence or absence of voicing, nasalization, aspiration, and other features. Thus, in articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the upper vocal tract, the upper vocal tract being defined as that part of the vocal tract that lies above the larynx. Consonants contrast with vowels.

Since the number of consonants in the world's languages is much greater than the number of consonant letters in any one alphabet, linguists have devised systems such as the International Phonetic Alphabet (IPA) to assign a unique symbol to each attested consonant. In fact, the Latin alphabet, which is used to write English, has fewer consonant letters than English has consonant sounds, so digraphs like "ch", "sh", "th", and "zh" are used to extend the alphabet, and some letters and digraphs represent more than one consonant. For example, many speakers are not aware that the sound spelled "th" in "this" is a different consonant than the "th" sound in "thing". (In the IPA they are transcribed ð and θ, respectively).

The word consonant comes from Latin oblique stem cōnsonant-, from cōnsonāns (littera) "sounding-together (letter)", a loan translation of Greek σύμφωνον sýmphōnon. As originally conceived by Plato, sýmphōna were specifically the stop consonants, described as "not being pronounceable without an adjacent vowel sound". Thus the term did not cover continuant consonants, which occur without vowels in a minority of languages, for example at the ends of the English words bottle and button. (The final vowel letters e and o in these words are only a product of orthography; Plato was concerned with pronunciation.) However, even Plato's original conception of consonant is inadequate for the universal description of human language, since the modern conception of consonant does not require cooccurrence with vowels.

Each consonant can be distinguished by several features:

• The manner of articulation is the method that the consonant is articulated, such as nasal (through the nose), stop (complete obstruction of air), or approximant (vowel like).

• The place of articulation is where in the vocal tract the obstruction of the consonant occurs, and which speech organs are involved. Places include bilabial (both lips), alveolar (tongue against the gum ridge), and velar (tongue against soft palate). Additionally, there may be a simultaneous narrowing at another place of articulation, such as palatalisation or pharyngealisation.

• The phonation of a consonant is how the vocal cords vibrate during the articulation. When the vocal cords vibrate fully, the consonant is called voiced; when they do not vibrate at all, it's voiceless.

• The voice onset time (VOT) indicates the timing of the phonation. Aspiration is a feature of VOT.

• The airstream mechanism is how the air moving through the vocal tract is powered. Most languages have exclusively pulmonic egressive consonants, which use the lungs and diaphragm, but ejectives, clicks, and implosives use different mechanisms.

• The length is how long the obstruction of a consonant lasts. This feature is borderline distinctive in English, as in "wholly" [hoʊlli] vs. "holy" [hoʊli], but cases are limited to morpheme boundaries.

• The articulatory force is how much muscular energy is involved. This has been proposed many times, but no distinction relying exclusively on force has ever been demonstrated.

All English consonants can be classified by a combination of these features, such as "voiceless alveolar stop consonant" [t]. 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.

The word consonant is also used to refer to a letter of an alphabet that denotes a consonant sound. Consonant letters in the English alphabet are B, C, D, F, G, H, J, K, L, M, N, P, Q, R, S, T, V, X, Z, and usually W and Y: The letter Y stands for the consonant [j] in "yoke", and for the vowel [ɪ] in "myth", for example; W is almost always a consonant except in rare words (mostly loanwords from Welsh) like "crwth" "cwm".

In linguistics (articulatory phonetics), manner of articulation describes how the tongue, lips, jaw, and other speech organs are involved in making a sound make contact. Often the concept is only used for the production of consonants. For any place of articulation, there may be several manners, and therefore several homorganic consonants. One parameter of manner is stricture, that is, how closely the speech organs approach one another. Parameters other than stricture are those involved in the [ar] sounds (taps and trills), and the sibilancy of fricatives. Often nasality and laterality are included in manner, but phoneticians such as Peter Ladefoged consider them to be independent.