tarnish🔊

Oxidation or discoloration, especially of a decorative metal exposed to air.

To oxidize or discolor due to oxidation.

To compromise, damage, soil, or sully.

(figurative) To lose its lustre or attraction; to become dull.

(copyright) To use a sign, image, expression, etc. sufficiently close to a trademarked one that it brings disrepute to it.