noun
iron ball
A ball made of iron, often used in sports like shot put or as a weapon in fiction.
砲丸投げでは、鉄球を遠くに投げる。
In shot put, you throw an iron ball as far as possible.
その戦士は鎖に付いた鉄球を振り回した。
The warrior swung an iron ball attached to a chain.
Compound of 鉄 (てつ, 'iron') and 球 (きゅう, 'ball').