/ Dictionary / Index P perborate: Meaning and Definition of Find definitions for: per•bo•rate Pronunciation: (pur-bôr'āt, -bōr'-), [key] — n. Chem. a salt of perboric acid, as sodium perborate, NaBO&multiplydot;4HO, used for bleaching, disinfecting, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. per annum perborax Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language