Anarchist
Part of speech: noun
Definition: One who believes in or advocates the absence of government in all forms (compare anarchism), especially one who works toward the realization of such. One who disregards laws and social norms as a form of rebellion against authority. By extension from previous sense, one who promotes chaos and lawlessness; a nihilist or terrorist. One who resents outside control or influence on his or her life, in particular a government, and therefore desires the absence of political control.
Example sentence: Anarchism means all sort of things to different people, but the traditional anarchists' movements assumed that there'd be a highly organized society, just one organized from below with direct participation and so on.
Nihilist
Part of speech: noun
Definition: A person who accepts or champions nihilism.An absolute skeptic; a person who believes in the truth of nothing.