Definition of "trephine"

trephine

/tɹɪˈfaɪn/

noun
plural trephines
1. (medicine) A surgical instrument with a cylindrical blade used to remove a circular section of tissue, such as bone or cornea; a trepan.
verb
third-person singular simple present trephines, present participle trephining, simple past and past participle trephined
1. (intransitive) To use a trephine during surgery.
  Quotations
  "We shall wait," said Van Helsing, "just long enough to fix the best spot for trephining, so that we may most quickly and perfectly remove the blood clot, for it is evident that the haemorrhage is increasing."
  1897, Bram Stoker, chapter 21, in Dracula
2. (transitive) To perforate with a trephine.
  Quotations
  The pony was cast, and trephined, a middle-sized trephine (or bone saw) being used, which removed a circular piece of bone about the size of a two shilling piece, from the face immediately over the air cavity.
  1901 August 16, “Veterinary Departmental Report for May, 1901”, in The Agricultural Journal and Mining Record‎, volume 4, number 12, page 382