A soldier
a veteran
A military scientist
A person who studies ancient weapons might be a military historian, or might be an archaeologist. There is more than one reason to study ancient weapons.
The person who flies a jet is commonly referred to as a pilot. More specifically, if they are flying a commercial jet, they might be called an airline pilot. In the military context, they may be referred to as a fighter pilot or military pilot, depending on the type of aircraft they operate.
Furlough.
They did (and still do) call those guys civilians.
you call this person a "confidante"
You call the person a victim.
you call them a tired person =-=-= or you could call them asleep
A person who is not a member of the military or the police force.
A Fleet
Reveille