lathe dog
A mechanical clamp used to drive a workpiece on a lathe. Technical term; not common in everyday conversation.
旋盤で加工するときは、回し金でワークを固定する。
When machining on a lathe, secure the workpiece with a lathe dog.
Compound of 回し (mawashi, 'turning') + 金 (kane, 'metal'). The exact historical derivation is uncertain, but the term refers to a metal turning tool.