/ Dictionary / Index D der.: Meaning and Definition of Find definitions for: der. Pronunciation: [key] derivation. derivative. derive. derived. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: der (Thesaurus) De Quincey deracinate Related Content Daily Word Quiz: garrulous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language