The Collaborative International Dictionary of English v.0.48:

nonviolence \nonviolence\ n.
   The theory, doctrine, or practice of peaceful resistance to a
   government by fasting or refusing to cooperate.

   Syn: passive resistance.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

nonviolence
    n 1: peaceful resistance to a government by fasting or refusing
         to cooperate [syn: passive resistance, nonviolent
         resistance, nonviolence]