crinoid vs sea lily

crinoid and sea lily both are nouns.

Word	Noun	Adjective	Verb	Adverb
crinoid	Yes	Yes	No	No
sea lily	Yes	No	No	No

As nouns, sea lily is a hyponym of crinoid; that is, sea lily is a word with a more specific, narrower meaning than crinoid:

crinoid: primitive echinoderms having five or more feathery arms radiating from a central disk
sea lily: crinoid with delicate radiating arms and a stalked body attached to a hard surface

Other hyponyms of crinoid include comatulid, feather star.

crinoid (noun)	sea lily (noun)
primitive echinoderms having five or more feathery arms radiating from a central disk	crinoid with delicate radiating arms and a stalked body attached to a hard surface

crinoid (adjective)	sea lily (adjective)
of or relating to or belonging to the class Crinoidea