T'ARNISHED, participle passive Sullied; having lost its brightness by oxydation, or by some alteration induced by exposure to air, dust and the like. Gold and silver, when tarnished resume their brightness by setting them over certain lyes. Copper and pewter, etc. tarnished recover their luster with tripoli and potashes.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI