sleep vs eternal sleep

sleep and eternal sleep both are nouns.

Word	Noun	Adjective	Verb	Adverb
sleep	Yes	No	Yes	No
eternal sleep	Yes	No	No	No

As nouns, sleep and eternal sleep are synonyms defined as:

sleep and eternal sleep: euphemisms for death (based on an analogy between lying in a bed and in a tomb)

Other synonyms of sleep include eternal rest, quietus, rest.

sleep (noun)	eternal sleep (noun)
a natural and periodic state of rest during which consciousness of the world is suspended	euphemisms for death (based on an analogy between lying in a bed and in a tomb)
euphemisms for death (based on an analogy between lying in a bed and in a tomb)
a torpid state resembling deep sleep
a period of time spent sleeping

sleep (verb)	eternal sleep (verb)
be asleep
be able to accommodate for sleeping