deviationism

/ˌdiviˈeɪʃəˌnɪzəm/
noun
  1. A political or ideological belief that differs from the official or accepted position of a group, especially in a political party or movement.
    • Deviationism was seen as a threat to the unity of the organization.
    • Historians study the role of deviationism in the early communist movements.
    • The party expelled members accused of deviationism for opposing the leader's policies.