haddock vs finnan

haddock and finnan both are nouns.

Word	Noun	Adjective	Verb	Adverb
haddock	Yes	No	No	No
finnan	Yes	No	No	No

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

haddock: lean white flesh of fish similar to but smaller than cod; usually baked or poached or as fillets sauteed or fried
finnan: haddock usually baked but sometimes broiled with lots of butter

Other hyponyms of haddock include finnan haddie, finnan haddock, smoked haddock.

haddock (noun)	finnan (noun)
important food fish on both sides of the Atlantic; related to cod but usually smaller	haddock usually baked but sometimes broiled with lots of butter
lean white flesh of fish similar to but smaller than cod; usually baked or poached or as fillets sauteed or fried