The Collaborative International Dictionary of English v.0.48:

Payment \Pay"ment\, n. [F. payment, paiement. See Pay to
   requite.]
   1. The act of paying, or giving compensation; the discharge
      of a debt or an obligation.
      [1913 Webster]

            No man envieth the payment of a debt. --Bacon.
      [1913 Webster]

   2. That which is paid; the thing given in discharge of a
      debt, or an obligation, or in fulfillment of a promise;
      reward; recompense; requital; return. --Shak.
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   3. Punishment; chastisement. [R.]
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WordNet (r) 3.0 (2006):

payment
    n 1: a sum of money paid or a claim discharged [ant: default,
         nonpayment, nonremittal]
    2: the act of paying money [syn: payment, defrayal,
       defrayment] [ant: evasion, nonpayment]
    3: an act of requiting; returning in kind [syn: requital,
       payment]