The Collaborative International Dictionary of English v.0.48:

Anarchist \An"arch*ist\, n. [Cf. F. anarchiste.]
   An anarch; one who advocates anarchy of aims at the overthrow
   of civil government.
   [1913 Webster]

WordNet (r) 3.0 (2006):

anarchist
    n 1: an advocate of anarchism [syn: anarchist, nihilist,
         syndicalist]