tankcar

Rail. Engin .: A large tank mounted on a platform truck, for carrying petroleum or other liquid. tank-engine, tank-locomotive, s . Rail. Engin.: An engine having a tank or tanks enabling it to carry a supply of water sufficient for its own consumption without a tender. Such are used for yard-engines, for side-lines of limited length, and for ascending grades with moderate loads. The boiler and machinery are carried on the driving-wheels, and the variable weight of water and fuel on the tank-truck.