Stain
Part of speech: noun
Definition: A discoloured spot or area. A blemish on one's character or reputation. A substance used to soak into a surface and colour it. A reagent or dye used to stain microscope specimens so as to make some structures visible.
Part of speech: verb
Definition: To discolour something To taint or tarnish someone's character or reputation To coat a surface with a stain To treat a microscope specimen with a dye
Example sentence: I have an unremovable stain of self-confidence.
Dirt
Part of speech: noun
Definition: Soil or earth.A stain or spot (on clothes etc); any foreign substance that worsens appearance.Previously unknown negative facts (or invented "facts") about a person, gossip.
Example sentence: There is no need to do any housework at all. After the first four years the dirt doesn't get any worse.