Emily Dickinson Lexicon

TRILL, n. [It. trillo; Dan. trille; G. triller; W. treilliaw, to turn, to roll. But the latter may be contracted from treiglaw, to turn; traill, traigyl, a turn or roll, from the root of draw, drag. Trill coincides with thirl and drill; D. drillen. Qu. reel.]

A quaver; a shake of the voice in singing, or of the sound of an instrument. [See Shake.]