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.
a tarnished coating.
tarnished condition; discoloration; alteration of the luster of a metal.
a stain or blemish.
Origin of tarnish
1590–1600; < Middle Frenchterniss-, long stem of ternir to dull, deaden, derivative of terne dull, wan < Germanic; compare Old High Germantarni, cognate with Old Saxonderni,Old Englishdierne hidden, obscure; see -ish2
1590s, from present participle stem of Middle French ternir "dull the luster or brightness of, make dim" (15c.), probably from Old French terne (adj.) "dull, dark," from a Germanic source cognate with Old High German tarnjan "to conceal, hide," Old English dyrnan "to hide, darken," from Proto-Germanic *darnjaz (see dern). Figurative sense is from 1690s. Related: Tarnished; tarnishing.