/ Dictionary / Index U underwire: Meaning and Definition of Find definitions for: un•der•wire Pronunciation: (un'dur-wīr"), [key] — n. a wire sewn into the underside of each cup of a brassiere, used for support and shape. a brassiere with such wires. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. underwing underwithhold Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language