collectable vs peculiarity

collectable and peculiarity both are nouns.

Word	Noun	Adjective	Verb	Adverb
collectable	Yes	Yes	No	No
peculiarity	Yes	No	No	No

As nouns, peculiarity is a hypernym of collectable; that is, peculiarity is a word with a broader meaning than collectable:

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

Other hypernyms of collectable include curio, curiosity, oddity, oddment, rarity.

collectable (noun)	peculiarity (noun)
things considered to be worth collecting (not necessarily valuable or antique)	something unusual -- perhaps worthy of collecting
	a distinguishing trait
	an odd or unusual characteristic

collectable (adjective)	peculiarity (adjective)
subject to or requiring payment especially as specified