nihilism
1. [ noun ] (politics) a revolutionary doctrine that advocates destruction of the social system for its own sake
Related terms: doctrine
2. [ noun ] (psychology,psychiatry) the delusion that things (or everything, including the self) do not exist; a sense that everything is unreal
Synonyms: nihilistic_delusion
Related terms: delusion
3. [ noun ] complete denial of all established authority and institutions
Related terms: anarchy