polychete worm vs annelid worm

polychete worm and annelid worm both are nouns.

Word	Noun	Adjective	Verb	Adverb
polychete worm	Yes	No	No	No
annelid worm	Yes	No	No	No

As nouns, annelid worm is a hypernym of polychete worm; that is, annelid worm is a word with a broader meaning than polychete worm:

polychete worm: chiefly marine annelids possessing both sexes and having paired appendages (parapodia) bearing bristles
annelid worm: worms with cylindrical bodies segmented both internally and externally

Other hypernyms of polychete worm include annelid, segmented worm.

polychete worm (noun)	annelid worm (noun)
chiefly marine annelids possessing both sexes and having paired appendages (parapodia) bearing bristles	worms with cylindrical bodies segmented both internally and externally