A munitions dump or munitions base was a storage area for munitions.
In 2267, in an act of sabotage, James T. Kirk and Spock used a sonic grenade to blow up a munitions dump outside Commander Kor's headquarters on Organia. (TOS: "Errand of Mercy")
In 2370, the Maquis constructed a munitions base on planetoid Alpha 441. (VOY: "Dreadnought")