Forms: 5–7 trepane, 5–6 trapane, 6 trappan(e, 7–8 trapan, 6– trepan. [a. F. trépan (also † trapan) a borer, surgical crown-saw (14th c.), ad. med.L. trepanum (Du Cange) a crown-saw, ad. Gr. τρύπανον a borer.]
1. A surgical instrument in the form of a crown-saw, for cutting out small pieces of bone, esp. from the skull.
c. 1400. Lanfranc’s Cirurg., 127. Þis schal be þe foorme of a trepane with þe whiche þe brayn scolle schal be trepaned wiþ.
1525. trans. Jerome of Brunswick’s Surg., xxxiv. H j/2. If the bone be stronge, bore ther throughe many holes with the trappane.
1676. Wiseman, Chirurg. Treat., V. ix. 393. I began to work with the Trepan, which I much prefer before a Trephine, it being an Instrument which doth its work lightly, and cutteth the Bone equally.
a. 1715. Burnet, Own Time, an. 1660 (1766). I. 146. The operation of the trepan and the cure was counted one of the greatest performances of surgery at that time.
1846. Brittan, trans. Malgaigne’s Man. Oper. Surg., 166. The trepan is applied to the cranium, sternum, and to the tibia, in cases of sequestrum. The scapula has also been trepanned, the os coccyx, the inferior maxila, &c.
† 2. A military engine formerly used in sieges: ? for boring holes in walls. Obs.
1584. Hudson, Du Bartas’ Judith, III. 107. And there th’ Inginers haue the Trepan drest, And reared vp the Ramme for battry best.
1608. Sylvester, Du Bartas, II. iv. IV. Decay, 994. There-under (safe) the Ram with yron horn,… The boistrous Trepane, and steel Pick-ax play Their parts apace, not idle night nor day.
1610. W. Folkingham, Art of Survey, I. xiii. 45. Engines … Militarie; as Battering-Rams,… Trepanes.
3. A boring instrument for sinking shafts. (Usually treated as F., trépan.)
1877. Knight, Dict. Mech., Trepan... 2. (French.) A workman’s name for the steel at the foot of a boring rod.
1903. Illustr. Lond. News, 10 Oct., 528. The great boring instrument or trêpan, rises and falls with a regular motion.
1903. Daily Chron., 22 Oct., 3/5. An 18 ft. shaft has reached a depth of nearly 1,100 ft., the small trépan having gone much further down.
4. attrib., as trepan hole, a hole made in a bone by a trepan; trepan saw, a saw of the form of a trepan, a crown-saw.
1839. Ure, Dict. Arts, 148. A is a pulley…. It has the crown or trepan saw a fixed to it.
1899. Allbutt’s Syst. Med., VII. 239. A piece of metal tubing … is screwed into the trepan hole.
