1) Discolor 2) To darken 3) To make black or obscure 
clouded or tinged with brown; obscured; cloudy brown colour
• (v. t.) To darken; to make black; to obscure.
In·fus'cate transitive verb [ Latin infuscatus , past participle of infuscare ; prefix in- in + fuscare to make dark, from fuscus dark.] To darken; to make black; to obscure. 
[v] - darken with a brownish tinge, as of insect wings
verb darken with a brownish tinge, as of insect wings
darkened with a fuscous or brownish tinge.