The Collaborative International Dictionary of English v.0.48:

Persecution \Per`se*cu"tion\, n. [F. pers['e]cution, L.
   persecutio.]
   1. The act or practice of persecuting; especially, the
      infliction of loss, pain, or death for adherence to a
      particular creed or mode of worship.
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            Persecution produces no sincere conviction. --Paley.
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   2. The state or condition of being persecuted. --Locke.
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   3. A carrying on; prosecution. [Obs.]
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WordNet (r) 3.0 (2006):

persecution
    n 1: the act of persecuting (especially on the basis of race or
         religion)