/ Dictionary / Index U underbred: Meaning and Definition of Find definitions for: un•der•bred Pronunciation: (un"dur-bred'), [key] — adj. having inferior breeding or manners; vulgar. not of pure breed, as a horse. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: underbred (Thesaurus) underboss underbrush Related Content Daily Word Quiz: apogee Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language