‖ xanthosisPath.|zænˈθəʊsɪs| [mod.L., f.Gr. ξανθός yellow: see -osis.] (See quots.) 1857Dunglison Med.Lex., Xanthosis, a term applied to the yellow discolouration often observed in cancerous tumours.1890Billings Nat.Med.Dict., Xanthosis, formation of a yellow skin or pigment.