aeruginous
/ɪəˈruːdʒɪnəs/(also aerugineous) In early use Medicine, in later use chiefly Botany
adjective
Of the nature or colour of verdigris; containing or characterized by basic copper carbonate; bluish-green.
Origin
Late Middle English; earliest use found in Guy de Chauliac's Grande Chirurgie. From Anglo-Norman and Middle French erugineux, French érugineux (of bile or other bodily humours) of the colour of verdigris, covered with verdigris, of a colour similar to verdigris and its etymon classical Latin aerūginōsus rusty, in post-classical Latin also of a rusty colour from aerūgin-, aerūgō + -ōsus.