trill

(trĭl)

1. A fluttering or tremulous sound, as that made by certain birds; a warble.
2. Music
   a. The rapid alternation of two tones either a whole or a half tone apart.
   b. A vibrato.
3. Linguistics
   a. A rapid vibration of one speech organ against another, as of the tongue against the alveolar ridge in Spanish rr.
   b. A speech sound pronounced with such a vibration.

1. To sound, sing, or play with a trill.
2. To articulate (a sound) with a trill.