Debuccalization

Debuccalization is a sound change in which an oral consonant loses its original place of articulation and moves it to the glottis (usually [h], [ɦ], or [ʔ]). The pronunciation of a consonant as [h] is sometimes called aspiration but in phonetics, aspiration is the burst of air accompanying a stop. The word comes from Latin bucca, meaning "cheek".

Debuccalization is usually seen as a sub-type of lenition, often defined as a consonant mutation involving the weakening of a consonant by progressive shifts in pronunciation.

Debuccalization processes occur in many different types of environments such as the following:

/q/ is debuccalized to /ʔ/ in several Arabic varieties, such as Egyptian Arabic.

Most English-speakers in England and many speakers of American English debuccalize /t/ to a glottal stop [ʔ] in two environments: in word-final position before another consonant

and before a syllabic [n̩] following /l/, /r/, /n/, or a vowel. Here the /t/ may also be nasally released.

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