harasser

from WordNet (r) 3.0 (2006)

harasser
    n 1: a persistent tormentor
    2: a persistent attacker; "the harassers were not members of the
       regular army" [syn: {harasser}, {harrier}]

from The Collaborative International Dictionary of English v.0.48

Harasser \Har"ass*er\ (-[~e]r), n.
   One who harasses.
   [1913 Webster]

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