/ Dictionary / Index U underside: Meaning and Definition of Find definitions for: un•der•side Pronunciation: (un'dur-sīd"), [key] — n. an under or lower side. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: underside (Thesaurus) undershrub undersign Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language