A surgical instrument with a cylindrical saw usually used for removing a disk of bone, especially from the skull, or for removing corneal tissue.
tr.v. tre·phined, tre·phin·ing, tre·phines
To operate on with a trephine.
[French tréphine, from obsolete English trefine, from Latin trēs fīnēs, three ends : trēs, three; see trei- in the Appendix of Indo-European roots + fīnēs, pl. of fīnis, end.]
treph′i·nation (trĕf′ə-nāshən) n.
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