collectible vs curiosity

collectible and curiosity both are nouns.

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

As nouns, curiosity is a hypernym of collectible; that is, curiosity is a word with a broader meaning than collectible:

collectible: things considered to be worth collecting (not necessarily valuable or antique)
curiosity: something unusual -- perhaps worthy of collecting

Other hypernyms of collectible include curio, oddity, oddment, peculiarity, rarity.

collectible (noun)	curiosity (noun)
things considered to be worth collecting (not necessarily valuable or antique)	something unusual -- perhaps worthy of collecting
	a state in which you want to learn more about something

collectible (adjective)	curiosity (adjective)
subject to or requiring payment especially as specified