Source : Webster's Revised Unabridged Dictionary (1913)

Stain \Stain\, v. i.
   To give or receive a stain; to grow dim.

Stain \Stain\, n.
   1. A discoloration by foreign matter; a spot; as, a stain on
      a garment or cloth. --Shak.

   2. A natural spot of a color different from the gound.

            Swift trouts, diversified with crimson stains.
                                                  --Pope.

   3. Taint of guilt; tarnish; disgrace; reproach.

            Nor death itself can wholly wash their stains.
                                                  --Dryden.

            Our opinion . . . is, I trust, without any blemish
            or stain of heresy.                   --Hooker.

   4. Cause of reproach; shame. --Sir P. Sidney.

   5. A tincture; a tinge. [R.]

            You have some stain of soldier in you. --Shak.

   Syn: Blot; spot; taint; pollution; blemish; tarnish; color;
        disgrace; infamy; shame.

Stain \Stain\, v. t. [imp. & p. p. {Stained}; p. pr. & vb. n.
   {Staining}.] [Abbrev. fr. distain.]
   1. To discolor by the application of foreign matter; to make
      foul; to spot; as, to stain the hand with dye; armor
      stained with blood.

   2. To color, as wood, glass, paper, cloth, or the like, by
      processess affecting, chemically or otherwise, the
      material itself; to tinge with a color or colors combining
      with, or penetrating, the substance; to dye; as, to stain
      wood with acids, colored washes, paint rubbed in, etc.; to
      stain glass.

   3. To spot with guilt or infamy; to bring reproach on; to
      blot; to soil; to tarnish.

            Of honor void, Of innocence, of faith, of purity,
            Our wonted ornaments now soiled and stained.
                                                  --Milton.

   4. To cause to seem inferior or soiled by comparison.

            She stains the ripest virgins of her age. --Beau. &
                                                  Fl.

            That did all other beasts in beauty stain.
                                                  --Spenser.

   {Stained glass}, glass colored or stained by certain metallic
      pigments fused into its substance, -- often used for
      making ornament windows.

   Syn: To paint; dye; blot; soil; sully; discolor; disgrace;
        taint.

   Usage: {Paint}, {Stain}, {Dye}. These denote three different
          processes; the first mechanical, the other two,
          chiefly chemical. To paint a thing is so spread a coat
          of coloring matter over it; to stain or dye a thing is
          to impart color to its substance. To stain is said
          chiefly of solids, as wood, glass, paper; to dye, of
          fibrous substances, textile fabrics, etc.; the one,
          commonly, a simple process, as applying a wash; the
          other more complex, as fixing colors by mordants.

Source : WordNet®

stain
     n 1: a soiled or discolored appearance; "the wine left a dark
          stain" [syn: {discoloration}, {discolouration}]
     2: (microscopy) a dye or other coloring material that is used
        in microscopy to make structures visible
     3: the state of being covered with unclean things [syn: {dirt},
         {filth}, {grime}, {soil}, {grease}, {grunge}]
     4: a symbol of disgrace or infamy; "And the Lord set a mark
        upon Cain"--Genesis [syn: {mark}, {stigma}, {brand}]
     5: an act that brings discredit to the person who does it; "he
        made a huge blot on his copybook" [syn: {blot}, {smear}, {smirch},
         {spot}]
     v 1: color with a liquid dye or tint; "Stain this table a
          beautiful walnut color"; "people knew how to stain glass
          a beautiful blue in the middle ages"
     2: produce or leave stains; "Red wine stains the table cloth"
     3: make dirty or spotty, as by exposure to air; also used
        metaphorically; "The silver was tarnished by the long
        exposure to the air"; "Her reputation was sullied after
        the affair with a married man" [syn: {tarnish}, {maculate},
         {sully}, {defile}]
     4: color for microscopic study; "The laboratory worker dyed the
        specimen"