meringue vs topping

meringue and topping both are nouns.

Word	Noun	Adjective	Verb	Adverb
meringue	Yes	No	No	No
topping	Yes	Yes	No	No

As nouns, topping is a hypernym of meringue; that is, topping is a word with a broader meaning than meringue:

meringue: sweet topping especially for pies made of beaten egg whites and sugar
topping: a flavorful addition on top of a dish

meringue (noun)	topping (noun)
sweet topping especially for pies made of beaten egg whites and sugar	a flavorful addition on top of a dish

meringue (adjective)	topping (adjective)
	excellent; best possible