| n. | 1. | (Surg.) An instrument for trepanning, being an improvement on the trepan. It is a circular or cylindrical saw, with a handle like that of a gimlet, and a little sharp perforator called the center pin. |
| v. t. | 1. | To perforate with a trephine; to trepan. |
| Noun | 1. | trephine - a surgical instrument used to remove sections of bone from the skull Synonyms: trepan |
| Verb | 1. | trephine - operate on with a trephine |