/ Dictionary / Index U underived: Meaning and Definition of Find definitions for: un•de•rived Pronunciation: (un"di-rīvd'), [key] — adj. not derived; fundamental, as an axiom or postulate; immediate. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: underived (Thesaurus) underinsure underlaid Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language