/ Dictionary / Index U uncommon: Meaning and Definition of Find definitions for: un•com•mon Pronunciation: (un-kom'un), [key] — -er, -est. not common; unusual; rare: an uncommon word. unusual in amount or degree; above the ordinary: an uncommon amount of mail. exceptional; remarkable. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: uncommon (Thesaurus) uncommitted uncommonly Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language