/ Dictionary / Index C carboxyl group: Meaning and Definition of Find definitions for: carbox'yl group" Pronunciation: [key] the univalent radical COOH, present in and characteristic of organic acids. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. carboxylation carboxylic acid Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language