piazza vs plaza

piazza and plaza both are nouns.

Word	Noun	Adjective	Verb	Adverb
piazza	Yes	No	No	No
plaza	Yes	No	No	No

As nouns, piazza and plaza are synonyms defined as:

Other synonyms of piazza include place.

piazza (noun)	plaza (noun)
a public square with room for pedestrians	mercantile establishment consisting of a carefully landscaped complex of shops representing leading merchandisers; usually includes restaurants and a convenient parking area; a modern version of the traditional marketplace
	a public square with room for pedestrians