siphonophore vs nanomia

siphonophore and nanomia both are nouns.

Word	Noun	Adjective	Verb	Adverb
siphonophore	Yes	No	No	No
nanomia	Yes	No	No	No

As nouns, nanomia is a hyponym of siphonophore; that is, nanomia is a word with a more specific, narrower meaning than siphonophore:

siphonophore: a floating or swimming oceanic colony of polyps often transparent or showily colored
nanomia: small creatures resembling pieces of fuzzy rope; each with a cluster of swimming bells serving as the head and long elastic tentacles for drawing in prey

Other hyponyms of siphonophore include jellyfish, man-of-war, Portuguese man-of-war, praya, apolemia.

siphonophore (noun)	nanomia (noun)
a floating or swimming oceanic colony of polyps often transparent or showily colored	small creatures resembling pieces of fuzzy rope; each with a cluster of swimming bells serving as the head and long elastic tentacles for drawing in prey