A consonant is a speech sound such as B, F, T, or M that is articulated with complete or partial closure of the upper vocal tract, which in turn partially or completely interrupts the airflow.

 

Consonants can be described and distinguished from each other by whether they are voiced or not, where they are placed, and how they're articulated.

 

Voicing

Some consonants are "voiced", in other words involve vibration of the vocal folds, while others aren't. For example, both "p" and "b" are made by closing the lips briefly to stop the flow of air and then releasing it. But of the two only "b" is voiced.

 

Placement

This has to do with where in the vocal tract – extending from the lips to the glottis – the air flow is obstructed. The key regions of articulation used to contrast phonemes in English are, from to back and then down the vocal tract are:

 

labial (lips) – as in the first and last consonants of "pop".

 

labio-dental (teeth and lips) – as in first consonant of "fun".

 

dental (or linguo-dental since in English these consonants are formed by placing the tongue between the teeth) – as in the "th" of "this".

 

alveolar (the ridge just behind the upper teeth) – as in the first and last consonants of "ten".

 

post-alveolar (or palato-alveolar because it's the region between the alveolar ridge and the hard palate) – as in the "sh" of "shoe".

 

palatal (pertaining to the hard palate, or roof of the mouth) – as in the first consonant of "yes".

 

velar (pertaining to the soft palate or velum) – as in the first consonant of "cat".

 

glottal (the region of the vocal cords and the opening between them) – as in the first consonant of "hat".

 

Manner of articulation

This has to do with how much the air flow is obstructed in forming the sound. Consonants can involve anything from a complete obstruction of the airflow, as in "p" or "k", to a very slight obstruction as in "w" or "j". The main forms of articulation in sounding phonemes in English, starting with those involving the most obstruction, are:

 

plosive (complete obstruction followed by release) – as in the first consonant of "ten".

 

fricative (very close but not complete obstruction involving friction) – as in the first consonant of "set".

 

affricate (very close obstruction where the consonant begins as a plosive and ends as a fricative) – as in the "ch" of "chair".

 

nasal (complete obstruction of the air flow in the mouth but with the velum open so that air can escape from the nose producing a humming sound) – as in first and last consonants of "man".

 

approximant (some obstruction but not enough to cause friction). These consonants are sometimes further divided into two types:

 

    · liquids - as in the "l" of let, where the tongue touches the alveolar ridge but the air is allowed to flow freely past the sides of the tongue and the "r" of ride where the tongue approaches the palate.

 

    · glides (a very slight closure, almost like a vowel) – as in the "w" of wet and the "j" of yet. Glide consonants are sometimes called semi-vowels.

 

See also a vowel.