RhymeZone: trills definitions

Definitions of trill:

noun: a note that alternates rapidly with another note a semitone above it
verb: pronounce with a trill, of the phoneme `r'
Example: "Some speakers trill their r's"
verb: sing or play with trills, alternating with the half note above or below
name: A surname (very rare: popularity rank in the U.S.: #67026)