The Collaborative International Dictionary of English v.0.48:

Discount \Dis"count`\ (?; 277), v. t. [imp. & p. p.
   Discounted; p. pr. & vb. n. Discounting.] [OF. desconter,
   descompter, to deduct, F. d['e]compter to discount; pref.
   des- (L. dis-) + conter, compter. See Count, v.]
   1. To deduct from an account, debt, charge, and the like; to
      make an abatement of; as, merchants sometimes discount
      five or six per cent for prompt payment of bills.
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   2. To lend money upon, deducting the discount or allowance
      for interest; as, the banks discount notes and bills of
      exchange.
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            Discount only unexceptionable paper.  --Walsh.
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   3. To take into consideration beforehand; to anticipate and
      form conclusions concerning (an event).
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   4. To leave out of account; to take no notice of. [R.]
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            Of the three opinions (I discount Brown's). --Sir W.
                                                  Hamilton.
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