/ Dictionary / Index S size-up: Meaning and Definition of Find definitions for: size-up Pronunciation: (sīz'up"), [key] — n. an appraisal or estimation, esp. as the result of sizing up: asking for a size-up of the new office equipment. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: size-up (Thesaurus) sizer sizing Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language