from The Century Dictionary.

  • noun An instrument for boring; a borer.
  • noun The name given by the French to a boring-tool used for sinking wells and mining shafts to great depths and sometimes of great dimensions.
  • noun An instrument, in the form of a crown-saw, used by surgeons for removing parts of the bones of the skull, in order to relieve the brain from pressure or irritation. The trephine is an improved form of this instrument. See cuts under crown-saw and trephine.
  • To perforate by a trepan, especially by the surgical trepan; operate on with a trepan.
  • See trapan.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Surg.) A crown-saw or cylindrical saw for perforating the skull, turned, when used, like a bit or gimlet. See trephine.
  • noun (Mining) A kind of broad chisel for sinking shafts.
  • verb (Surg.) To perforate (the skull) with a trepan, so as to remove a portion of the bone, and thus relieve the brain from pressure or irritation; to perform an operation with the trepan.
  • noun A snare; a trapan.
  • noun a deceiver; a cheat.
  • transitive verb To insnare; to trap; to trapan.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun archaic A trickster.
  • verb archaic To trick; to ensnare; to seduce.
  • noun A tool used to bore through rock when sinking shafts.
  • noun medicine A surgical instrument used to remove a circular section of bone from the skull; a trephine.
  • verb transitive, manufacturing, mining To create a large hole by making a narrow groove outlining the shape of the hole and then removing the plug of material remaining by less expensive means.
  • verb medicine To use a trepan; to trephine.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • verb cut a hole with a trepan, as in surgery
  • noun a surgical instrument used to remove sections of bone from the skull
  • noun a drill for cutting circular holes around a center


from Wiktionary, Creative Commons Attribution/Share-Alike License

Possibly from Old English treppan ("to trap").

from Wiktionary, Creative Commons Attribution/Share-Alike License

From French trephine.


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  • From the distracted and despairing man whom love and longing trepan from the lover under passion’s ban the prisoner of transport and distraction from this Kamar al-Zaman son of Shahriman to the peerless one of the fair Houris the pearl-union to the Lady Budur daughter of King Al Ghayur

    The Book of The Thousand Nights And A Night 2006

  • The "bizarre bits" on display here include a bunch of medical specimens and instruments, such as the smallpox scab, various saws used for amputations and neurosurgery, and a trepan, a grotesque device used to perforate the skull, which was believed to aid in treating mental illness, epilepsy and migraines.

    Virginia Historical Society's odd gems offer uncommon insights into the past 2011

  • Relatively humane compared to the older method of using a hammer that would trepan the animal.

    Think Progress » ThinkFast AM: June 20, 2006 2006

  • When a bone is broken, or cleft, or contused, or otherwise injured, and when by mistake it has not been discovered, and neither the raspatory nor trepan has been applied as required, but the case has been neglected as if the bone were sound, fever will generally come on if in winter, and in summer the fever usually seizes after seven days.

    On Injuries Of The Head 2007

  • And many of these require trepanning, but you must not apply the trepan to the sutures themselves, but on the adjoining bone.

    On Injuries Of The Head 2007

  • And if you wish to saw at once down to the membrane, and then remove the bone, you must also, in like manner, frequently take out the trepan and dip it in cold water.

    On Injuries Of The Head 2007

  • But you must take care where you apply the trepan, and see that you do so only where it appears to be particularly thick, and having fixed the instrument there, that you frequently make examinations and endeavor by moving the bone to bring it up.

    On Injuries Of The Head 2007

  • For the trepan being heated by running round, and heating and drying the bone, burns it and makes a larger piece of bone around the sawing to drop off, than would otherwise do.

    On Injuries Of The Head 2007

  • But if you have not charge of the treatment from the first, but undertake it from another after a time, you must saw the bone at once down to the meninx with a serrated trepan, and in doing so must frequently take out the trepan and examine with a sound (specillum), and otherwise along the tract of the instrument.

    On Injuries Of The Head 2007

  • And you must not trepan any of them, nor run any risks in attempting to extract the pieces of bone, until they rise up of their own accord, upon the subsidence of the swelling.

    On Injuries Of The Head 2007


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  • (noun/verb) - (1) A person who entraps or decoys others into actions or positions which may be to his advantage and to their ruin or loss. Also applied to an animal. --Sir James Murray's New English Dictionary, 1926 (2) A snare; from Trapani, a part of Italy where our ships, being insidiously invited on the reign of Queen Elizabeth, were unjustly detained. --Daniel Fenning's Royal English Dictionary, 1775

    February 7, 2018