The Collaborative International Dictionary
Somnific
Somnific \Som*nif"ic\, a. [L. somnificus; somnus sleep + facere to make.] Causing sleep; somniferous.
Wiktionary
somnific
a. Causing sleep; somniferous.
WordNet
somnific
adj. sleep inducing [syn: soporific, soporiferous, somniferous, hypnogogic, hypnagogic]
Usage examples of "somnific".
He felt a sort of cool and queer-smelling breeze in his face, and had just enough ability for analytical thought left in his consciousness to tell him that some somnific gas must be coming through the heater vents.