black swan
noun
1- a mainly black swan with white flight feathers which is common in Australia and Tasmania and has been introduced widely elsewhere黑天鹅。
1.1
- Cygnus atratus, family Anatidae.拉丁名Cygnus atratus,鸭科。
1.2
- archaic a thing or kind of person that is extremely rare〈古〉稀世之物（或人）：
husbands without faults, if such black swans there be.
完美无缺的丈夫, 假如有如此人间尤物的话。
ORIGIN: proverbial, from Juvenal's Satires.