/ Dictionary / Index T theremin: Meaning and Definition of Find definitions for: ther•e•min Pronunciation: (ther'u-min), [key] — n. a musical instrument with electronic tone generation, the pitch and tone volume being controlled by the distance between the player's hands and two metal rods serving as antennas. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: theremin (Thesaurus) thereinto thereof Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language