/ Dictionary / Index D def: Meaning and Definition of Find definitions for: def Pronunciation: (def), [key] — adv. Informal. definitely: Going to Europe this summer? But def! def Pronunciation: (def), [key] excellent: That hip-hop record is def! def. Pronunciation: [key] defective. defendant. defense. deferred. defined. definite. definition. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. de-excite deface Related Content Daily Word Quiz: supercilious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language