barbiturate: organic compound having powerful soporific effect; overdose can be fatal
sedative-hypnotic: a sedative that depresses activity of the central nervous system and reduces anxiety and induces sleep
volt: a unit of potential equal to the potential difference between two points on a conductor carrying a current of 1 ampere when the power dissipated between the two points is 1 watt; equivalent to the potential difference across a resistance of 1 ohm when 1 ampere of current flows through it