Visits by presidential candidates are a rarity here.
Bananas, once rarities in Soviet states, are now widely available.
He is that rarity: a true man of science.
The importance of the find lies in its rarity.
英语词典包含67175条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。