/ Dictionary / Index H hydroxy acid: Meaning and Definition of Find definitions for: hydrox'y ac'id Pronunciation: [key] an organic acid containing both a carboxyl and a hydroxyl group. any of a class of organic acids containing a hydroxyl group and showing properties of both an alcohol and an acid. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hydroxyacetic acid hydroxyapatite Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language