militia

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An army composed of ordinary citizens rather than professional soldiers.
• noun A military force that is not part of a regular army and is subject to call for service in an emergency.
• noun The whole body of physically fit civilians eligible by law for military service.

from The Century Dictionary.

• noun Military service; warfare.
• noun Soldiery; militants collectively.
• noun Hence The whole body of men declared by law amenable to military service, without enlistment, whether armed and drilled or not.
• noun A body of men enrolled and drilled according to military law, as an armed force, but not as regular soldiers, and called out in emergency for actual service and periodically for drill and exercise.

from the GNU version of the Collaborative International Dictionary of English.

• noun In the widest sense, the whole military force of a nation, including both those engaged in military service as a business, and those competent and available for such service; specifically, the body of citizens enrolled for military instruction and discipline, but not subject to be called into actual service except in emergencies.
• noun obsolete Military service; warfare.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun this sense?) An army.
• noun in particular An army of trained civilians, which may be an official reserve army, called upon in time of need, the entire able-bodied population of a state which may also be called upon, or a private force not under government control.
• noun The national police force of certain countries (e.g. Russia, Ukraine).

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the entire body of physically fit civilians eligible by law for military service
• noun civilians trained as soldiers but not part of the regular army