tank iron

Webster's Dictionary (GCIDE)

1.A large basin or cistern; an artificial receptacle for liquids. [1913 Webster]

2.A pond, pool, or small lake, natural or artificial. [Webster 1913 Suppl.]

We stood in the afterglow on the bank of the tank and saw the ducks come home.— F. Remington.

The tanks are full and the grass is high.— Lawson.[Webster 1913 Suppl.]

3.(Mil.) a heavily armored combat vehicle which moves on caterpillar treads, rather than wheels. It typically carries a cannon and a heavy machine, and sometimes other weapons. It is the main distinguishing weapon of an armored division. [PJC]

4.a jail cell for temporarily holding prisoners, as in a police station. [PJC]

Tank engine, a locomotive which carries the water and fuel it requires, thus dispensing with a tender.

Tank iron, plate iron thinner than boiler plate, and thicker than sheet iron or stovepipe iron.

Tank worm (Zool.), a small nematoid worm found in the water tanks of India, supposed by some to be the young of the Guinea worm. [1913 Webster]