stain - noun

a soiled or discolored appearance

(microscopy) a dye or other coloring material that is used in microscopy to make structures visible

the state of being covered with unclean things

a symbol of disgrace or infamy

an act that brings discredit to the person who does it

stain - verb

• color with a liquid dye or tint
• produce or leave stains
• make dirty or spotty, as by exposure to air; also used metaphorically
• color for microscopic study

stain - thesaurus

blot   brand   defile   dirt   discoloration   discolouration   filth   grease   grime   grunge   maculate   mark   smear   smirch   soil   spot   stigma   sully   tarnish