The Collaborative International Dictionary of English v.0.48:

Mutineer \Mu"ti*neer`\, n. [See Mutiny.]
   One guilty of mutiny.
   [1913 Webster]

WordNet (r) 3.0 (2006):

mutineer
    n 1: someone who is openly rebellious and refuses to obey
         authorities (especially seamen or soldiers)

Moby Thesaurus II by Grady Ward, 1.0:

43 Moby Thesaurus words for "mutineer":
   agitator, anarch, anarchist, anarcho-syndicalist, antinomian,
   arise, brawler, extremist, frondeur, insubordinate, insurge,
   insurgent, insurrect, insurrectionary, insurrectionist, insurrecto,
   malcontent, maverick, mount the barricades, mutiny, nihilist,
   nonconformist, overthrow, rebel, reluct, reluctate, revolt,
   revolter, revolute, revolution, revolutionary, revolutionist,
   revolutionize, riot, rioter, rise, rise up, run riot, strike,
   subversive, subvert, syndicalist, traitor