/ Dictionary / Index T theorem: Meaning and Definition of Find definitions for: the•o•rem Pronunciation: (thē'ur-um, thēr'um), [key] — n. a theoretical proposition, statement, or formula embodying something to be proved from other propositions or formulas. a rule or law, esp. one expressed by an equation or formula. a proposition that can be deduced from the premises or assumptions of a system. an idea, belief, method, or statement generally accepted as true or worthwhile without proof. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: theorem (Thesaurus) Theorell theorem of the mean Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language