nautilus vs nuclear-powered submarine

nautilus and nuclear-powered submarine both are nouns.

Word	Noun	Adjective	Verb	Adverb
nautilus	Yes	No	No	No
nuclear-powered submarine	Yes	No	No	No

As nouns, nautilus and nuclear-powered submarine are synonyms defined as:

nautilus and nuclear-powered submarine: a submarine that is propelled by nuclear power

Other synonyms of nautilus include nuclear submarine.

nautilus (noun)	nuclear-powered submarine (noun)
cephalopod of the Indian and Pacific oceans having a spiral shell with pale pearly partitions	a submarine that is propelled by nuclear power
cephalopod mollusk of warm seas whose females have delicate papery spiral shells
a submarine that is propelled by nuclear power