/ Dictionary / Index C costuming: Meaning and Definition of Find definitions for: cos•tum•ing Pronunciation: (kos't-ming, -ty-), [key] — n. material for costumes. costumes collectively. the act of furnishing or designing costumes. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: costuming (Thesaurus) costumier cost unit Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language