/ Dictionary / Index U undershirt: Meaning and Definition of Find definitions for: un•der•shirt Pronunciation: (un'dur-shûrt"), [key] — n. a collarless, usually pullover undergarment for the torso, usually of cotton and either sleeveless and low-cut or with sleeves, worn chiefly by men and children. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: undershirt (Thesaurus) undersheriff undershoot 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