noun

1. A military establishment for the storing, development, manufacturing, testing, or repairing of arms, ammunition, and other war materiel; an armoury.

2. A stock of weapons, especially all the weapons that a nation possesses.

3. A store or supply of anything.

4. Any 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."