Flap

Flap is a sound articulated in such a way that one articulator, usually the tongue tip, is drawn back and then allowed to strike against another articulator in returning to its rest position (cf. Ladefoged (1975))

Example

in American English /r/ in mirror or /t/ in dirty are often flaps.

Link

Utrecht Lexicon of Linguistics

References

• Ladefoged 1975. A course in phonetics, Harcourt Brace Jovanovich, New York.