pizza vs Sicilian pizza

pizza and Sicilian pizza both are nouns.

Word	Noun	Adjective	Verb	Adverb
pizza	Yes	No	No	No
Sicilian pizza	Yes	No	No	No

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

pizza: Italian open pie made of thin bread dough spread with a spiced mixture of e.g. tomato sauce and cheese
Sicilian pizza: pizza made with a thick crust

Other hyponyms of pizza include sausage pizza, pepperoni pizza, cheese pizza, anchovy pizza.

pizza (noun)	Sicilian pizza (noun)
Italian open pie made of thin bread dough spread with a spiced mixture of e.g. tomato sauce and cheese	pizza made with a thick crust