/ Dictionary / Index U undermost: Meaning and Definition of Find definitions for: un•der•most Pronunciation: (un'dur-mōst"), [key] — adj., adv. lowest, as in position, status, or the like. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. undermine underneath 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