trill

A fluttering or tremulous sound, as that made by certain birds; a warble.

The rapid alternation of two tones either a whole or a half tone apart.

A vibrato.

A rapid vibration of one speech organ against another, as of the tongue against the alveolar ridge in Spanish rr.

A speech sound pronounced with such a vibration.

To sound, sing, or play with a trill.

To articulate (a sound) with a trill.

To produce or give forth a trill.