/ Dictionary / Index P powerful: Meaning and Definition of Find definitions for: pow•er•ful Pronunciation: (pou'ur-ful), [key] — adj. having or exerting great power or force. physically strong, as a person: a large, powerful athlete. producing great physical effects, as a machine or a blow. potent; efficacious: a powerful drug. having great effectiveness, as a speech, speaker, description, reason, etc. having great power, authority, or influence; mighty: a powerful nation. great in number or amount: a powerful lot of money. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: powerful (Thesaurus) power forward powerhouse Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language