dumpling vs matzo ball

dumpling and matzo ball both are nouns.

Word	Noun	Adjective	Verb	Adverb
dumpling	Yes	No	No	No
matzo ball	Yes	No	No	No

As nouns, matzo ball is a hyponym of dumpling; that is, matzo ball is a word with a more specific, narrower meaning than dumpling:

Other hyponyms of dumpling include gnocchi, matzah ball, matzoh ball, won ton, wonton.

dumpling (noun)	matzo ball (noun)
small balls or strips of boiled or steamed dough	a Jewish dumpling made of matzo meal; usually served in soup
dessert made by baking fruit wrapped in pastry