unleavened bread vs matzo

unleavened bread and matzo both are nouns.

Word	Noun	Adjective	Verb	Adverb
unleavened bread	Yes	No	No	No
matzo	Yes	No	No	No

As nouns, unleavened bread and matzo are synonyms defined as:

Other synonyms of unleavened bread include matzah, matzoh.

unleavened bread (noun)	matzo (noun)
brittle flat bread eaten at Passover	brittle flat bread eaten at Passover