What does "flapping" refer to in phonetics?

Flapping refers to a quick tap articulation of alveolar stops, particularly in American English. This phonetic phenomenon occurs when a /t/ or /d/ sound occurs between two vowel sounds, where the first vowel is typically stressed, and the second vowel is unstressed. Instead of pronouncing the consonants as distinct stops, the tongue quickly taps the alveolar ridge, resulting in a sound that is often perceived as a soft 'd' sound. For example, in the words "butter" or "ladder," the /t/ and /d/ are pronounced as a flap, creating a smooth, fluid transition between the vowels.

This feature contributes to the natural flow of speech in American accents, making it a crucial aspect of phonology that helps differentiate among dialects. Understanding flapping is essential for recognizing patterns in spoken language and its implications for both speech production and perception.