Breadcrumb Home > Dictionary > Index P peroxyacid: Meaning and Definition of Find definitions for: per•ox•y•ac•id Pronunciation: (pu-rok"sē-as'id), [key] — n. Chem. an acid derived from hydrogen peroxide and containing the –O–O– group, as peroxysulfuric acid, HSO. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. peroxy peroxyborate ✖ Related Content Daily Word Quiz: sophism Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language