Belgian endive vs endive

Belgian endive and endive both are nouns.

Word	Noun	Adjective	Verb	Adverb
Belgian endive	Yes	No	No	No
endive	Yes	No	No	No

As nouns, endive is a hypernym of Belgian endive; that is, endive is a word with a broader meaning than Belgian endive:

Belgian endive: young broad-leaved endive plant deprived of light to form a narrow whitish head
endive: variety of endive having leaves with irregular frilled edges

Other hypernyms of Belgian endive include chicory escarole, escarole.

Belgian endive (noun)	endive (noun)
young broad-leaved endive plant deprived of light to form a narrow whitish head	variety of endive having leaves with irregular frilled edges
	widely cultivated herb with leaves valued as salad green; either curly serrated leaves or broad flat ones that are usually blanched