1. (n.) Nothingness; nihility.

2. (n.) The doctrine that nothing can be known; skepticism as to all knowledge and all reality.

3. (n.) The theories and practices of the Nihilists.

Jacobinism New Left Old Left agnosia anarchism anarcho-syndicalism anarchy antinomianism block blocking chaos confusion criminal syndicalism cynicism defeatism delirium delusion delusion of persecution dismalness disorder disorderliness disorganization disorientation disruption extreme left extreme left wing extremism flight of ideas gloominess gloomy outlook hallucination hallucinosis left-wing extremism lynch law malism mental block mental confusion misrule mob law mob rule mobocracy negativism nihilistic delusion ochlocracy paralogia pessimism primal chaos psychological block radicalism radicalization rebellion retreatism revolution revolutionism sans-culotterie sans-culottism syndicalism tohubohu turmoil ultraconservatism ultraism uncheerfulness unruliness