somnific
adj 1: sleep inducing [syn: {soporific}, {soporiferous},
{somniferous}, {somnific}, {hypnogogic}, {hypnagogic}]
Somnific \Som*nif"ic\, a. [L. somnificus; somnus sleep + facere
to make.]
Causing sleep; somniferous.
[1913 Webster]