v. & n.
v. 1 tr. & intr. discolour or be discoloured by the action of liquid sinking in. 2 tr. sully, blemish, spoil, damage (a reputation, character, etc.). 3 tr. colour (wood, glass, etc.) by a process other than painting or covering the surface. 4 tr. impregnate (a specimen) for microscopic examination with colouring matter that makes the structure visible by being deposited in some parts more than in others. 5 tr. print colours on (wallpaper).
n. 1 a discoloration, a spot or mark caused esp. by contact with foreign matter and not easily removed (a cloth covered with tea-stains). 2 a a blot or blemish. b damage to a reputation etc. (a stain on one's character). 3 a substance used in staining. stained glass dyed or coloured glass, esp. in a lead framework in a window (also (with hyphen) attrib.: stained-glass window). stainable adj. stainer n.
[ ME f. distain f. OF desteindre desteign- (as DIS-, TINGE) ]