/ Dictionary / Index C copper arsenite: Meaning and Definition of Find definitions for: cop'per ar'senite Pronunciation: [key] a yellowish-green, water-insoluble, poisonous powder, CuHAsO, used chiefly as a pigment and as an insecticide. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. copperah copperas Related Content Daily Word Quiz: laudable Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language