Definition of STAIN

  1. (noun)a soiled or discolored appearance
  2. (noun)(microscopy) a dye or other coloring material that is used in microscopy to make structures visible
  3. (noun)anything regarded as making something unclean
  4. (noun)a symbol of disgrace or infamy
  5. (noun)an act that brings discredit to the person who does it
  6. (verb)color with a liquid dye or tint
  7. (verb)produce or leave stains
  8. (verb)make dirty or spotty, as by exposure to air; also used metaphorically
  9. (verb)color for microscopic study