/ Dictionary / Index C colcothar: Meaning and Definition of Find definitions for: col•co•thar Pronunciation: (kol'ku-thur), [key] — n. Chem. the brownish-red oxide of iron produced by heating ferrous sulfate: used chiefly as a pigment in paints and theatrical rouge, and as a polishing agent. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Colchis cold Related Content Daily Word Quiz: mongrel Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language