Insurgent

1. noun

   a person who takes part in an armed rebellion against the constituted authority (especially in the hope of improving conditions)

   Similar: insurrectionist, freedom fighter, rebel

2. noun

   a member of an irregular armed force that fights a stronger force by sabotage and harassment

   Similar: guerrilla, guerilla, irregular

3. adjective

   in opposition to a civil authority or government

   Similar: seditious, subversive