/ Dictionary / Index U unfounded: Meaning and Definition of Find definitions for: un•found•ed Pronunciation: (un-foun'did), [key] — adj. without foundation; not based on fact, realistic considerations, or the like: unfounded suspicions. not established; not founded: the prophet of a religion as yet unfounded. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: unfounded (Thesaurus) unfortunate unfreeze Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language