/ Dictionary / Index A amobarbital: Meaning and Definition of Find definitions for: am•o•bar•bi•tal Pronunciation: (am"ō-bär'bi-tal", -tôl"), [key] — n. Pharm. a colorless, crystalline barbiturate, CHNO, used chiefly as a sedative. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: amobarbital (Thesaurus) amn't amoeba Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language