/ Dictionary / Index U uncle: Meaning and Definition of Find definitions for: un•cle Pronunciation: (ung'kul), [key] — n. a brother of one's father or mother. an aunt's husband. a familiar title or term of address for any elderly man. a pawnbroker. (cap.)Uncle Sam. a word formerly used in communications to represent the letter U. to concede defeat: They ganged up on him in the schoolyard and made him say uncle. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: uncle (Thesaurus) unclassy unclean Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language