Stain  —v. 1 discolour or be discoloured by the action of liquid sinking in. 2 spoil, damage (a reputation, character, etc.). 3 colour (wood, glass, etc.) With a penetrating substance. 4 impregnate (a specimen) with a colouring agent for microscopic examination. —n. 1 discoloration; spot, mark. 2 blot, blemish; damage to a reputation etc. 3 substance used in staining. [earlier distain from french desteindre]