fiesta vs luau

fiesta and luau both are nouns.

Word	Noun	Adjective	Verb	Adverb
fiesta	Yes	No	No	No
luau	Yes	No	No	No

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

fiesta: an elaborate party (often outdoors)
luau: an elaborate Hawaiian feast or party (especially one accompanied by traditional foods and entertainment)

Other hyponyms of fiesta include potlatch.

fiesta (noun)	luau (noun)
an elaborate party (often outdoors)	an elaborate Hawaiian feast or party (especially one accompanied by traditional foods and entertainment)