Definition of "Stain" :

noun: an act that brings discredit to the person who does it

noun: a soiled or discolored appearance

"The wine left a dark stain."

noun: a symbol of disgrace or infamy

noun: the state of being covered with unclean things

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

verb: color for microscopic study

verb: color with a liquid dye or tint

"Stain this table a beautiful walnut color."

verb: produce or leave stains

"Red wine stains the table cloth."

verb: make dirty or spotty, as by exposure to air; also used metaphorically