insurgent

noun | \ in-ˈsər-jənt \ | in·sur·gent

1. : a person who rises in revolt against civil authority or an established government; especially : one not recognized as a belligerent : one not recognized as a belligerent

2. : one that acts contrary to the established leadership (as of a political party, union, or corporation) or its decisions and policies

adjective

1. : rising in opposition to civil or political authority or against an established government