/ Dictionary / Index T thereof: Meaning and Definition of Find definitions for: there•of Pronunciation: (âr"uv', -ov'), [key] — adv. of that or it. from or out of that origin or cause. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: thereof (Thesaurus) theremin thereon 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