Collins COBUILD Advanced Learner's English Dictionary - rarity

(rarities) 1. If someone or something is a rarity, they are interesting or valuable because they are so unusual. (JOURNALISM) Sontag has always been that rarity, a glamorous intellectual... N-COUNT: usu sing, oft N in/among n 2. The rarity of something is the fact that it is very uncommon. It was a real prize due to its rarity and good condition... N-UNCOUNT: oft with poss