Tank

A Tank is an armoured fighting vehicle designed for front-line combat which combines operational mobility and tactical offensive and defensive capabilities. It may refer to the following:
 * Scorpion Tank- The UNSC Main Battle Tank.
 * Rhino- A possible tank deployed by UNSC.
 * Wraith- The Covenant Main Battle Tank.
 * Type-52 Anti-Aircraft Artillery- Anti-Air variant from the Wraith.

Tank can also refer an enclosed heavily armed unit.
 * Flood Tank Form- A Flood Pure Form derived from a mutating Stalker Form.

Tank could also refer to a container, usually for holding liquids, sometimes for compressed gases (gas tank).
 * Methane Tank- Place made for Grunts to breathe without their Suit.