Armory

From Memory Alpha, the free Star Trek reference

The armory, or weapons room, of a starship or other facility was a secured location where weapons and other offensive or defensive devices are stored securely to prevent unauthorized personnel from gaining access.

A starship often had several armories located in various areas of the ship. On some vessels, armories also hold photon torpedoes and other ship-based weapons. They were typically manned by an armory officer.

Vor'cha-class starships also possessed armories. After being taken over by the Saltah'na energy spheres, Captain Tel-Peh of the IKS Toh'Kaht seized the armory, which Hon-Tihl's forces were not able to take control of. (DS9: "Dramatis Personae")

Deep Space 9 possessed an armory, which Odo was to have his Bajoran Militia officers report to after he managed to persuade Weyoun to allow them to carry weapons. (DS9: "A Time to Stand")