Trill, n. [It. trillo, fr. trillare. See Trill to shake.]
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.