The difference between Armour and Tank

Armour as a noun (uncountable):

A protective layer over a body, vehicle, or other object intended to deflect or diffuse damaging forces.

Armour as a noun (uncountable):

A natural form of this kind of protection on an animal's body.

Armour as a noun (uncountable):

Metal plate, protecting a ship, military vehicle, or aircraft.

Armour as a noun (countable):

A tank, or other heavy mobile assault vehicle.

Armour as a noun (military, uncountable):

A military formation consisting primarily of tanks or other armoured fighting vehicles, collectively.

Armour as a noun (hydrology, uncountable):

The naturally occurring surface of pebbles, rocks or boulders that line the bed of a waterway or beach and provide protection against erosion.

Armour as a verb (transitive):

To equip something with armour or a protective coating or hardening.

Armour as a verb (transitive):

To provide something with an analogous form of protection.

Tank as a noun:

A closed container for liquids or gases.

Tank as a noun:

An open container or pool for storing water or other liquids.

Tank as a noun:

A pond, pool, or small lake, natural or artificial.

Tank as a noun:

The fuel reservoir of a vehicle.

Tank as a noun:

The amount held by a container; a tankful.

Tank as a noun:

An armoured fighting vehicle, armed with a gun in a turret, and moving on caterpillar tracks.

Tank as a noun (Australian and Indian English):

A reservoir or dam.

Tank as a noun (Southwestern US, chiefly, Texas):

A large metal container for holding drinking water for animals, usually placed near a wind-driven water pump, in an animal pen or field.

Tank as a noun (Southwestern US, chiefly, Texas):

By extension a small pond for the same purpose.

Tank as a noun (slang):

A very muscular and physically imposing person. Somebody who is built like a tank.

Tank as a noun (role-playing games, board games, video games):

a unit or character designed primarily around damage absorption and holding the attention of the enemy (as opposed to dealing damage, healing, or other tasks)

Tank as a noun (US, slang):

A prison cell, or prison generally.

Tank as a verb:

To fail or fall (often used in describing the economy or the stock market); to degenerate or decline rapidly; to plummet.

Tank as a verb (video games):

To attract the attacks of an enemy target in cooperative team-based combat, so that one's teammates can defeat the enemy in question more efficiently.

Tank as a verb:

To put fuel into a tank.

Tank as a verb:

To deliberately lose a sports match with the intent of gaining a perceived future competitive advantage.

Tank as a verb (fandom slang):

To resist damage; to be attacked without being hurt.

Tank as a noun:

A small Indian dry measure, averaging 240 grains in weight.

Tank as a noun:

A Bombay weight of 72 grains, for pearls.