SOMNIFEROUS
soporific, soporiferous, somniferous, somnific, hypnogogic, hypnagogic
(adjective) sleep inducing
Source: WordNet® 3.1
Etymology
Adjective
somniferous (comparative more somniferous, superlative most somniferous)
(pharmaceutical effect) causing or inducing sleep, normally with harmful overtones.
Synonyms
• See also soporific
Antonyms
• See also invigorating
Source: Wiktionary
Som*nif"er*ous, a. Etym: [L. somnifer; somnus sleep + ferre to
bring.]
Definition: Causing or inducing sleep; soporific; dormitive; as, a
somniferous potion. Walton.
Source: Webster’s Unabridged Dictionary 1913 Edition