The word "un-oppressive" means not oppressive, unjust, or cruel. Its antonyms can be oppressive, tyrannical, authoritarian, dictatorial, despotic, autocratic, harsh, severe, and cruel. Oppressive refers to anything that burdens, suppresses or controls the freedom of others. Tyrannical implies a cruel and unfair exercise of power. Authoritarian refers to a leader or regime that demands complete obedience. Dictatorial, despotic, and autocratic refer to rulers who exercise their power without regard for the will of the people. Harsh refers to anything that is severe or unkind. Lastly, cruel refers to anything that causes pain or suffering without any sense of pity or remorse.