Meaning

noun a collection of resources

noun all the weapons and equipment that a country has

noun a military structure where arms and ammunition and other military equipment are stored and training is given in the use of arms

originFrom Middle English armerie, armurie, armorye, from Anglo-Norman armurrie, from armure (“arms, armor”) + -ie (“-y”). By surface analysis, armour + -y.

Etymology from Wiktionary, CC BY-SA 3.0