agent orange agent noun • agent provocateur · · · Info · Definitions · Characters · · agent orange · · Text Common · · Latin · · Scripts 12 · · Length 4 · · Syllables Definitions · · · (noun) a herbicide used in the Vietnam War to defoliate forest areas. Synonyms: Agent Orange. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 e latin small letter e U+0065 g latin small letter g U+0067 n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 t latin small letter t U+0074