curiosity vs showpiece

curiosity and showpiece both are nouns.

Word	Noun	Adjective	Verb	Adverb
curiosity	Yes	No	No	No
showpiece	Yes	No	No	No

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

curiosity: something unusual -- perhaps worthy of collecting
showpiece: the outstanding item (the prize piece or main exhibit) in a collection

curiosity (noun)	showpiece (noun)
something unusual -- perhaps worthy of collecting	the outstanding item (the prize piece or main exhibit) in a collection
a state in which you want to learn more about something