/ Dictionary / Index A abaptiston: Meaning and Definition of Find definitions for: ab•ap•tis•ton Pronunciation: (ab"ap-tis'tun), [key] — n. a cone-shaped trephine designed to avoid penetration of the brain when incising the skull. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. abandonee à bas* Related Content Daily Word Quiz: lyceum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language