carboxyl carboxyhemoglobin • carboxylase · · · Info · Definitions · Synonyms · Characters · · carboxyl · · Text Latin · · Script 8 · · Length 3 · · Syllables Definitions · · · (noun) the univalent radical -COOH; present in and characteristic of organic acids. Synonyms: carboxyl group. · · Noun Definition 1 (adj) relating to or containing the carboxyl group or carboxyl radical. Synonyms: carboxylic. · · Adjective Definition 1 Synonyms · · · carboxyl group · · Synonym 1 carboxylic · · Synonym 2 Characters · · a latin small letter a U+0061 b latin small letter b U+0062 c latin small letter c U+0063 l latin small letter l U+006C o latin small letter o U+006F r latin small letter r U+0072 x latin small letter x U+0078 y latin small letter y U+0079