bonefish vs soft-finned fish

bonefish and soft-finned fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
bonefish	Yes	No	No	No
soft-finned fish	Yes	No	No	No

As nouns, soft-finned fish is a hypernym of bonefish; that is, soft-finned fish is a word with a broader meaning than bonefish:

bonefish: slender silvery marine fish found in tropical mud flats and mangrove lagoons
soft-finned fish: any fish of the superorder Malacopterygii

Other hypernyms of bonefish include malacopterygian.

bonefish (noun)	soft-finned fish (noun)
slender silvery marine fish found in tropical mud flats and mangrove lagoons	any fish of the superorder Malacopterygii