Trill

v. i.	1.	To flow in a small stream, or in drops rapidly succeeding each other; to trickle. And now and then an ample tear trilled down Her delicate cheek. - Shak. Whispered sounds Of waters, trilling from the riven stone. - Glover.
v. t.	1.	To turn round; to twirl. Bid him descend and trill another pin. - Chaucer.
	1.	To impart the quality of a trill to; to utter as, or with, a trill; as, to trill the r; to trill a note. [imp. & p. p. Trilled ; p. pr. & vb. n. Trilling.] The sober-suited songstress trills her lay. - Thomson.
v. i.	1.	To utter trills or a trill; to play or sing in tremulous vibrations of sound; to have a trembling sound; to quaver. To judge of trilling notes and tripping feet. - Dryden.
n.	1.
	1.	A sound, of consonantal character, made with a rapid succession of partial or entire intermissions, by the vibration of some one part of the organs in the mouth - tongue, uvula, epiglottis, or lip - against another part; as, the r is a trill in most languages.
	2.	The action of the organs in producing such sounds; as, to give a trill to the tongue. d
	3.	(Mus.) A shake or quaver of the voice in singing, or of the sound of an instrument, produced by the rapid alternation of two contiguous tones of the scale; as, to give a trill on the high C. See Shake.

Noun	1.	trill - a note that alternates rapidly with another note a semitone above it Synonyms: shake
Verb	1.	trill - pronounce with a trill, of the phoneme `r'; "Some speakers trill their r's"
	2.	trill - sing or play with trills, alternating with the half note above or below Synonyms: warble, quaver