trocar
/ˈtrəʊkɑː(r)/noun
- a surgical instrument with a three-sided cutting point enclosed in a tube, used for withdrawing fluid from a body cavity套针, 套管针（用于从体腔抽液的外科手术用具）。
词源
early 18th cent.: from French trocart, trois-quarts, from trois 'three' + carre 'side, face of an instrument'.