From Longman Dictionary of Contemporary Englishrarityrar‧i‧ty /ˈreərəti $ ˈrer-/ noun (plural rarities) 1 → be a rarity2 [countable]RARE something that is valuable or interesting because it is rare Some of these plants are national rarities.3 [uncountable]RARE the quality of being rare Such stamps are expensive because of their rarity.
Examples from the Corpus
rarity• Breadwinner wives who are the couple's sole earners are a rarity, wives are typically joint but secondary earners.• Moreover, stage performances of opera had been a rarity during the war.• This disease although now a rarity, does warrant a brief description.• Although once a rarity, the alto flute is now frequently found in modern orchestras.• Among wild creatures rarity is a relative condition, not always determined on the basis of actual numbers.• And he was that greater rarity, a Moses without political ambition.• That sheep dip is singularly disagreeable to a golden eagle is one reason for its rarity.• The Go-Gos' latest album is packed with live versions, B-sides, and other rarities.• That left him with one explanation for the rarity of polygamy in sparrows: The senior wives do not stand for it. 