soporiferous vs somnific

soporiferous and somnific both are adjectives.

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

As adjectives, soporiferous and somnific are synonyms defined as:

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

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