A military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g. communism during cold war era, supporting or promoting economic expansion through imperialism, and as a form of internal social control. As an adjective the term "military" is also used to refer to any property or aspect of a military. Militaries often function as societies within societies, by having their own military communities.

Adjective

military (comparative more military, superlative most military)

1. Characteristic of members of the armed forces.
   • 1891, Arthur Conan Doyle, “The Boscombe Valley Mystery”, in The Adventures of Sherlock Holmes:

     "My dear fellow, I know you well. I know the military neatness which characterises you. You shave every morning, and in this season you shave by the sunlight; but since your shaving is less and less complete as we get farther back on the left side, until it becomes positively slovenly as we get round the angle of the jaw, it is surely very clear that that side is less illuminated than the other. I could not imagine a man of your habits looking at himself in an equal light and being satisfied with such a result."

2. (North America) Relating to armed forces such as the army, marines, navy and air force (often as distinguished from civilians or police forces).
3. Relating to war.
   • 1989, Gregory Flynn, Soviet Military Doctrine and Western Policy‎, page 158:

     The only goal pursued by Western defense strategy — to cause the Warsaw Pact to break off an attack — is more military than political in nature.

4. Relating to armies or ground forces.

Noun military (plural military or militaries)

1. Armed forces.

   He spent six years in the military.

2. (US, with the) U.S. armed forces in general, including the Marine Corps.

   It's not the job of the military to make policy.