WordNet: curio, curiosity, oddity, oddment, peculiarity, rarity

something unusual -- perhaps worthy of collecting

• hypernym object, physical object

• hyponym bric-a-brac, knickknack, knickknackery, nicknack, whatnot

• hyponym collectable, collectible

• hyponym collector's item, piece de resistance, showpiece

curio

• (suomi) harvinaisuus (synonyymi)

curiosity

• (englanti) curious (derivationally related)
• (suomi) kuriositeetti (synonyymi)

oddity

• (englanti) odd (derivationally related)
• (suomi) harvinainen esine (synonyymi)

oddment

• (suomi) merkillisyys (synonyymi)

peculiarity

• (englanti) peculiar (derivationally related)
• (suomi) erikoisuus (synonyymi)

rarity

• (englanti) rare (derivationally related)
• (suomi) harvinaisuus (synonyymi)