The difference between Armoured train and Tank

Armoured train as a noun:

a railway train protected with armour

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.