somnific vs soporiferous

somnific and soporiferous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
somnific	No	Yes	No	No
soporiferous	No	Yes	No	No

As adjectives, somnific and soporiferous are synonyms defined as:

Other synonyms of somnific include hypnagogic, hypnogogic, somniferous, soporific.

somnific (adjective)	soporiferous (adjective)
sleep inducing	sleep inducing
	inducing mental lethargy