1
- chiefly historical a trephine (crown saw) used by surgeons for perforating the skull〈主史〉（在颅骨上开小孔用的）环钻, 环锯。
2
- a borer for sinking shafts矿井凿钻。
派生词
trepanation
/ˌtrepəˈneɪʃən/ noun词源
late Middle English: the noun via medieval Latin from Greek trupanon, from trupan 'to bore', from trupē 'hole'; the verb from Old French trepaner.