pentobarbital sodium pen·to·bar·bitalsodium uncommon noun 1. a barbiturate (trade name Nembutal) used as a sedative and hypnotic and anti-spasmodic Synonymspentobarbital sodiumpentobarbitalNembutalyellow jacket Related words Broader terms barbiturate WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
