vinegar eel vs eelworm

vinegar eel and eelworm both are nouns.

Word	Noun	Adjective	Verb	Adverb
vinegar eel	Yes	No	No	No
eelworm	Yes	No	No	No

As nouns, eelworm is a hypernym of vinegar eel; that is, eelworm is a word with a broader meaning than vinegar eel:

vinegar eel: minute eelworm that feeds on organisms that cause fermentation in e.g. vinegar
eelworm: any of various small free-living plant-parasitic roundworms

vinegar eel (noun)	eelworm (noun)
minute eelworm that feeds on organisms that cause fermentation in e.g. vinegar	any of various small free-living plant-parasitic roundworms