xan·tho·gen \ˈzan(t)thəjə̇n, -ˌjen\noun (-s) Etymology: International Scientific Vocabulary xanth- + -gen : either of two univalent radicals: a.: the radical C2H5OCSS− derived from xanthic acid (sense 1a) b.: the radical HOCSS− derived from xanthic acid (sense 2)