The Collaborative International Dictionary of English v.0.48:

Attaint \At*taint"\, v. t. [imp. & p. p. Attainted; p. pr. &
   vb. n. Attainting.] [OE. atteynten to convict, fr. atteynt,
   OF. ateint, p. p. of ateindre, ataindre. The meanings 3, 4,
   5, and 6 were influenced by a supposed connection with taint.
   See Attain, Attainder.]
   1. To attain; to get act; to hit. [Obs.]
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   2. (Old Law) To find guilty; to convict; -- said esp. of a
      jury on trial for giving a false verdict. [Obs.]
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            Upon sufficient proof attainted of some open act by
            men of his own condition.             --Blackstone.
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   3. (Law) To subject (a person) to the legal condition
      formerly resulting from a sentence of death or outlawry,
      pronounced in respect of treason or felony; to affect by
      attainder.
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            No person shall be attainted of high treason where
            corruption of blood is incurred, but by the oath of
            two witnesses.                        --Stat. 7 & 8
                                                  Wm. III.
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   4. To accuse; to charge with a crime or a dishonorable act.
      [Archaic]
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   5. To affect or infect, as with physical or mental disease or
      with moral contagion; to taint or corrupt.
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            My tender youth was never yet attaint
            With any passion of inflaming love.   --Shak.
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   6. To stain; to obscure; to sully; to disgrace; to cloud with
      infamy.
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            For so exceeding shone his glistring ray,
            That Ph?bus' golden face it did attaint. --Spenser.
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            Lest she with blame her honor should attaint.
                                                  --Spenser.
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