to dull the luster of (a metallic surface), especially by oxidation; discolor.
to diminish or destroy the purity of; stain; sully: The scandal tarnished his reputation.
verb (used without object)
to grow dull or discolored; lose luster.
to become sullied.
noun
a tarnished coating.
tarnished condition; discoloration; alteration of the luster of a metal.
a stain or blemish.
Origin of tarnish
1590–1600; <Middle French terniss-, long stem of ternir to dull, deaden, derivative of terne dull, wan <Germanic; compare Old High German tarni, cognate with Old Saxon derni,Old English dierne hidden, obscure; see -ish2
He said Iran pays lobbyists in Washington to discredit reports by Iranian exiles and tarnish their image.
White House Debunks Iran Nuclear Explosion, But Iran Denies Planting Story|Dan Ephron|January 29, 2013|DAILY BEAST
In response, Netanyahu said Olmert was trying to tarnish his administration ahead of parliamentary elections next week.
Explosive Allegations against Israeli Prime Minister Benjamin Netanyahu|Dan Ephron|January 16, 2013|DAILY BEAST
And using charges themselves false in order to tarnish his reputation?
A False Charge Against Fareed Zakaria (UPDATED)|David Frum|August 14, 2012|DAILY BEAST
Banville may tarnish his hero a bit, particularly by tormenting him with alcohol.
Can Pulp Win the Booker?|Allen Barra|September 7, 2011|DAILY BEAST
The aluminum utensils will be always shining, for the material of which they are made will not tarnish.
The American Country Girl|Martha Foote Crow
He not only tried to tarnish the name of my mother as well as my own, but he did his best to ruin me financially.
The Day of Judgment|Joseph Hocking
Japanese gold does not tarnish so readily as "passing," which is in some respects superior to it.
Art in Needlework|Lewis F. Day
No words of mine shall be added here to tarnish upon the mirror of memory this image of a sacred death and a sacred friendship.
Life of John Keats|William Michael Rossetti
I am not a great lord, I have neither an historical name to tarnish, nor an immense fortune to lose.
The Widow Lerouge|Emile Gaboriau
British Dictionary definitions for tarnish
tarnish
/ (ˈtɑːnɪʃ) /
verb
to lose or cause to lose the shine, esp by exposure to air or moisture resulting in surface oxidation; discoloursilver tarnishes quickly
to stain or become stained; taint or spoila fraud that tarnished his reputation
noun
a tarnished condition, surface, or film
Derived forms of tarnish
tarnishable, adjectivetarnisher, noun
Word Origin for tarnish
C16: from Old French ternir to make dull, from terne lustreless, of Germanic origin; related to Old High German tarnen to conceal, Old English dierne hidden