Is military a proper or common noun?

Answer 1

The term 'military officers' is a common noun, a word for any military officers of any kind.

A proper noun is the name of a specific person, place, thing, or a title; for example:

• Joint Chiefs of Staff, US Army
• Military Road NW, Washington, DC or Officers Lake Road, Meridian, MS
• Cafe Military, Fort, Mumbai, MH, India or The Officers House, Haverfordwest, UK
• "The Officer's Wife", a novel by B. Sidney Smith or "Trinity: Military War Dog" by Ronie Kendig

Answer 2

The word military is a commonnoun, a general word for any armed force of a country or members of an armed force.

A proper noun is the name of a specific person, place, thing, or a title; for example:

• Bureau of Political-Military Affairs, US Department of State, Washington, DC
• Military Road, Niagara falls, NY
• The Military Museum of Southern New England, Danbury, CT

The word military is also an adjective used to describe a noun (military personnel, military time).