Source : Webster's Revised Unabridged Dictionary (1913)

Taint \Taint\, v. t.
   Aphetic form of {Attaint}.

Taint \Taint\, v. i.
   1. To be infected or corrupted; to be touched with something
      corrupting.

            I can not taint with fear.            --Shak.

   2. To be affected with incipient putrefaction; as, meat soon
      taints in warm weather.

Taint \Taint\, n.
   1. Tincture; hue; color; tinge. [Obs.]

   2. Infection; corruption; deprivation.

            He had inherited from his parents a scrofulous
            taint, which it was beyond the power of medicine to
            remove.                               --Macaulay.

   3. A blemish on reputation; stain; spot; disgrace.

Taint \Taint\, n. [Cf. F. atteinte a blow, bit, stroke. See
   {Attaint}.]
   1. A thrust with a lance, which fails of its intended effect.
      [Obs.]

            This taint he followed with his sword drawn from a
            silver sheath.                        --Chapman.

   2. An injury done to a lance in an encounter, without its
      being broken; also, a breaking of a lance in an encounter
      in a dishonorable or unscientific manner. [Obs.]

Taint \Taint\, v. i. [imp. & p. p. {Tainted}; p. pr. & vb. n.
   {Tainting}.]
   To thrust ineffectually with a lance. [Obs.]

Taint \Taint\, v. t.
   1. To injure, as a lance, without breaking it; also, to
      break, as a lance, but usually in an unknightly or
      unscientific manner. [Obs.]

            Do not fear; I have A staff to taint, and bravely.
                                                  --Massinger.

   2. To hit or touch lightly, in tilting. [Obs.]

            They tainted each other on the helms and passed by.
                                                  --Ld. Berners.

Taint \Taint\, v. t. [F. teint, p. p. of teindre to dye, tinge,
   fr. L. tingere, tinctum. See {Tinge}, and cf. {Tint}.]
   1. To imbue or impregnate with something extraneous,
      especially with something odious, noxious, or poisonous;
      hence, to corrupt; to infect; to poison; as, putrid
      substance taint the air.

   2. Fig.: To stain; to sully; to tarnish.

            His unkindness may defeat my life, But never taint
            my love.                              --Shak.

   Syn: To contaminate; defile; pollute; corrupt; infect;
        disease; vitiate; poison.

Source : WordNet®

taint
     n : the state of being contaminated [syn: {contamination}]
     v 1: place under suspicion or cast doubt upon; "sully someone's
          reputation" [syn: {defile}, {sully}, {corrupt}, {cloud}]
     2: contaminate with a disease or microorganism [syn: {infect}]
        [ant: {disinfect}]