sectarianism

noun2

1. •
   Rigid adherence to a particular sect, denomination, ideology, or party.

   • They were discussing sectarianism between Shias and Sunnis.
2. •
   A political system in which power is shared among religious sects based on a constitutional formula distributing public offices among these sects.

   • In Lebanese sectarianism, one half of the members of parliament are Christians and the other half are Muslims.