somnifacient

adjective

som·​ni·​fa·​cient ˌsäm-nə-ˈfā-shənt 

: hypnotic sense 1

somnifacient noun

Word History

Etymology

Latin somnus sleep + English -facient

First Known Use

circa 1890, in the meaning defined above

Medical Definition

somnifacient

1 of 2 adjective

som·​ni·​fa·​cient ˌsäm-nə-ˈfā-shənt 

: inducing sleep : hypnotic sense 1

a somnifacient drug

somnifacient

2 of 2 noun

: a somnifacient agent (as a drug) : hypnotic sense 1