/fee'noh bahr"bi tawl', -tal', -neuh-/ , n. Pharm.
a white, crystalline powder, C 12 H 12 N 2 O 3 , used as a sedative, a hypnotic, and as an antispasmodic in epilepsy.
Also, esp. Brit., phenobarbitone /fee'noh bahr"bi tohn', -neuh-/ . Also called phenylethylbarbituric acid .
[ 1915-20; PHENO- + BARBITAL ]