winter flounder vs winter flounder

winter flounder and winter flounder both are nouns.

Word	Noun	Adjective	Verb	Adverb
winter flounder	Yes	No	No	No
winter flounder	Yes	No	No	No

winter flounder (noun)	winter flounder (noun)
important American food fish in the winter	important American food fish in the winter
flesh of American flounder; important in the winter	flesh of American flounder; important in the winter