ultraleftism

noun

1. (uncountable, usually)The ideology of the ultraleft, associated with left communism, characterized by a rejection of both social democracy and state socialism in favor of traditional Marxism, including opposition to Leninism and the vanguard party.
2. (broadly, specifically, uncountable, usually)Italian left communism; Bordigism.
3. (derogatory, uncountable, usually)Extreme or uncompromising leftist ideology, especially strict adherence to orthodox Marxism.