ultraleftism

noun3

1. •
   (disapproving) Extreme or uncompromising leftist ideology, especially strict adherence to orthodox Marxism.
2. •
   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.
3. •
   Italian left communism; Bordigism.