trill
noun.
a note that alternates rapidly with another note a semitone above it
Synonym: shake
noun.
the articulation of a consonant (especially the consonant `r') with a rapid flutter of the tongue against the palate or uvula
he pronounced his R's with a distinct trill
verb.
pronounce with a trill, of the phoneme `r'
Some speakers trill their r's
verb.
sing or play with trills, alternating with the half note above or below
Synonym: quaver, warble