Definitions
1.nounA military establishment for the storing, development, manufacturing, testing, or repairing of arms, ammunition, and other war materiel; an armoury.
2.nounA stock of weapons, especially all the weapons that a nation possesses.
3.nounA store or supply of anything.
4.nounAny supply of aid collected to prepare a person or army for hardship"He arrived with a large arsenal of cleansers and tools, and got right to work."