I. ˈtär-nish verb
Etymology: Middle English ternysshen, from Middle French terniss-, stem of ternir, probably of Germanic origin; akin to Old High German tarnan to hide
Date: 15th century
transitive verb
1. : to dull or destroy the luster of by or as if by air, dust, or dirt : soil , stain
2.
a. : to detract from the good quality of : vitiate
his fine dreams now slightly tarnish ed
b. : to bring disgrace on : sully
the scandal has tarnish ed his reputation
intransitive verb
: to become tarnished
• tar·nish·able -ni-shə-bəl adjective
II. noun
Date: 1684
: something that tarnishes ; especially : a film of chemically altered material on the surface of a metal (as silver)