lose or cause to lose lustre, especially as a result of exposure to air or moisture (使)失去光泽 [no obj.]silver tarnishes too easily. 银很容易失去光泽。 [with obj.]lemon juice would tarnish the gilded metal. 柠檬汁会使镀金金属失去光泽。 ■(figurative)make or become less valuable or respected[with obj.] (喻)败坏;玷污 his regime had not been tarnished by human rights abuses. 他的政权并没有因为践踏人权而名誉受损。
noun
[mass noun]dullness of colour; loss of brightness 色泽单调;色泽变暗 ■a film or stain formed on an exposed surface of a mineral or metal (矿物,金属上的)失泽膜 ■(figurative)damage or harm done to something (喻)瑕疵,污点
派生 tarnishable adjective 语源
late Middle English (as a verb): from French terniss-, lengthened stem of ternir, from terne 'dark, dull'