A civilian is a person not a member of an armed force nor a person engaged in hostilities.

Non-combatant is a term of art in the law of war and international humanitarian law to refer to civilians who are not taking a direct part in hostilities; persons, such as combat medics and military chaplains, who are members of the belligerent armed forces but are protected because of their specific duties ; combatants who are placed hors de combat; and neutral persons, such as peacekeepers, who are not involved in fighting for one of the belligerents involved in a war. This particular status was first recognized under the Geneva Conventions with the First Geneva Convention of 1864.