holothurian vs echinoderm

holothurian and echinoderm both are nouns.

Word	Noun	Adjective	Verb	Adverb
holothurian	Yes	No	No	No
echinoderm	Yes	No	No	No

As nouns, echinoderm is a hypernym of holothurian; that is, echinoderm is a word with a broader meaning than holothurian:

holothurian: echinoderm having a flexible sausage-shaped body, tentacles surrounding the mouth and tube feet; free-living mud feeders
echinoderm: marine invertebrates with tube feet and five-part radially symmetrical bodies

holothurian (noun)	echinoderm (noun)
echinoderm having a flexible sausage-shaped body, tentacles surrounding the mouth and tube feet; free-living mud feeders	marine invertebrates with tube feet and five-part radially symmetrical bodies