What does armor mean?
The definition of armor
Ar”mor, n.
Etym: [OE. armure, fr. F. armure, OF. armeure, fr. L. armatura. See Armature.] [Spelt also armour.]

1 Defensive arms for the body; any clothing or covering worn to protect one’s person in battle.

Note: In English statues, armor is used for the whole apparatus of war, including offensive as well as defensive arms. The statues of armor directed what arms every man should provide.

2 Steel or iron covering, whether of ships or forts, protecting them from the fire of artillery. Coat armor, the escutcheon of a person or family, with its several charges and other furniture, as mantling, crest, supporters, motto, etc.

— Submarine, a water-tight dress or covering for a diver. See under Submarine.