Flapping

Flapping or tapping, also known as alveolar flapping or intervocalic flapping, is a phonological process found in many dialects of English, especially North American English, Australian English and New Zealand English, by which the consonants /t/ and sometimes also /d/ may be pronounced as a flap (tap) in certain positions, particularly between vowels (intervocalic position). In some cases, the effect is perceived by some listeners as the replacement of a /t/ sound with a /d/ sound; for example, the word butter pronounced with flapping may be heard as "budder". In fact, /t/ and sometimes /d/ are pronounced in such positions as an alveolar flap (or tap; IPA symbol [ɾ]), a sound produced by briefly tapping the alveolar ridge with the tongue. Also, in similar positions, the combination /nt/ may be pronounced with a nasalized flap or just [n] so winter may sound similar or identical to winner.

The terms flap and tap are often used synonymously, although some authors make a distinction between them. According to Heinz Giegerich, a flap involves a rapid movement of the tongue tip from a retracted vertical position to a (more or less) horizontal position, during which the tongue tip brushes the alveolar ridge, while a tap involves a rapid upward and downward movement of the tongue tip, the upward movement being voluntary and the lowering involuntary. On this view, the sound referred to here is the alveolar tap, rather than the flap, even though the term "flapping" is ingrained in much of the phonological literature.

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