A personal weapon or ordnance weapon is a weapon

Weapon

A weapon, arm, or armament is a tool or instrument used with the aim of causing damage or harm to living beings or artificial structures or systems...

 that is issued to an individual
member of a military or paramilitary unit, e.g. to individual infantry

Infantry

Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...

 soldiers, but also side arm

Side arm

A side arm is a weapon, usually a pistol but can be a dagger, as used in pre-modern times, which is worn on the body in a holster to permit immediate access and use. A side arm is typically required equipment for military personnel and sometimes carried by law enforcement personnel...

s carried by officers or other personnel.

These weapons in pre-modern contexts tend to be melee weapons (blade weapons or polearms), and in modern contexts usually firearms, but also blade weapons such as the bayonet

Bayonet

A bayonet is a knife, dagger, sword, or spike-shaped weapon designed to fit in, on, over or underneath the muzzle of a rifle, musket or similar weapon, effectively turning the gun into a spear...

 or the officer's sword.