tarpon vs ladyfish

tarpon and ladyfish both are nouns.

Word	Noun	Adjective	Verb	Adverb
tarpon	Yes	No	No	No
ladyfish	Yes	No	No	No

As nouns, ladyfish is a hyponym of tarpon; that is, ladyfish is a word with a more specific, narrower meaning than tarpon:

tarpon: large silvery game fish of warm Atlantic coastal waters especially off Florida
ladyfish: game fish resembling the tarpon but smaller

Other hyponyms of tarpon include Elops saurus, tenpounder.

tarpon (noun)	ladyfish (noun)
large silvery game fish of warm Atlantic coastal waters especially off Florida	game fish resembling the tarpon but smaller