/ Dictionary / Index T trephine: Meaning and Definition of Find definitions for: tre•phine Pronunciation: (tri-fīn', -fēn'), [key] — n., v., -phined, -phin•ing. —n. a small circular saw with a center pin mounted on a strong hollow metal shaft to which is attached a transverse handle: used in surgery to remove circular disks of bone from the skull. —v.t. to operate upon with a trephine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: trephine (Thesaurus) trepang trepid Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language