isopod vs sea slater

isopod and sea slater both are nouns.

Word	Noun	Adjective	Verb	Adverb
isopod	Yes	No	No	No
sea slater	Yes	No	No	No

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

isopod: any of various small terrestrial or aquatic crustaceans with seven pairs of legs adapted for crawling
sea slater: marine isopod crustacean

Other hyponyms of isopod include slater, wood louse, woodlouse, sea louse.

isopod (noun)	sea slater (noun)
any of various small terrestrial or aquatic crustaceans with seven pairs of legs adapted for crawling	marine isopod crustacean