Definify.com

Webster 1913 Edition

Adj.

[L.

aeruginosus

, fr.

aerugo

rust of copper, fr.

aes

copper: cf. F.

érugineux

Of the nature or color of verdigris, or the rust of copper.

See also: æruginous

aeruginous ‎(comparative more aeruginous, superlative most aeruginous)

Of or pertaining to copper-rust or verdigris.
There was definitely some aeruginous material on that door handle.