Phonological history of English consonants

This article describes those aspects of the phonological history of the English language which concern consonants.

The voiceless stops /p/, /t/, /k/ are typically aspirated when they begin a stressed syllable, becoming [pʰ], [tʰ], [kʰ], as described under English phonology (obstruents). There is some regional variation in the degree of aspiration, and in some Scottish and northern English accents aspiration does not occur at all.

In certain accents, such as Geordie (among younger women) and in some speakers of Dublin English, /p/, /t/ and /k/ can be preaspirated when they come at the end of a word or utterance, becoming [ʰp], [ʰt], [ʰk].

Flapping, or tapping, is a process whereby /t/ or /d/ is pronounced as the alveolar flap [ɾ] in certain positions, especially between vowels (but also sometimes after other sonorants). It may be perceived as, for example, the pronunciation of butter as "budder". It occurs especially in North American English (to varying extents) and in Australian and New Zealand English.

Apart from the T-voicing that results from flapping (described above), some dialects feature other instances of voicing or lenition of the stops /p/, /t/ and /k/. In Geordie, these stops may be fully voiced ([b], [d], [ɡ]) in intervocalic position. In Devon, stops and other obstruents may be voiced (or at least lenited) between vowels and when final after a weak vowel, so for example the /k/ and /t/ in jacket may approach the realizations [ɡ] and [d], making the word sound similar or identical to jagged.

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