topping vs icing

topping and icing both are nouns.

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

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

Other hyponyms of topping include frosting, ice, glaze, meringue, whipped cream, streusel.

topping (noun)	icing (noun)
a flavorful addition on top of a dish	(ice hockey) the act of shooting the puck from within your own defensive area the length of the rink beyond the opponent's goal
	a flavored sugar topping used to coat and decorate cakes
	the formation of frost or ice on a surface

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