lugworm vs polychete

lugworm and polychete both are nouns.

Word	Noun	Adjective	Verb	Adverb
lugworm	Yes	No	No	No
polychete	Yes	No	No	No

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

lugworm: marine worms having a row of tufted gills along each side of the back; often used for fishing bait
polychete: chiefly marine annelids possessing both sexes and having paired appendages (parapodia) bearing bristles

Other hypernyms of lugworm include polychaete, polychaete worm, polychete worm.

lugworm (noun)	polychete (noun)
marine worms having a row of tufted gills along each side of the back; often used for fishing bait	chiefly marine annelids possessing both sexes and having paired appendages (parapodia) bearing bristles