black swan

== English == === Etymology === From Middle English blak swan, calqued from a Latin quotation from Satire VI (written late 1st century – early 2nd century B.C.E.) of the Roman poet Juvenal: “Rara avis in terris, nigroque simillima cygno [a bird as rare upon the earth as a black swan]!”. Equivalent to black +‎ swan. Sense 2.1 (“something believed impossible or not to exist”) is from the fact that all swans were thought to have white plumage until black swans were discovered in Australia in the 17th century by Dutch explorers. Sense 2.2 (“rare and hard-to-predict event”) was popularized by the Lebanese-American author Nassim Nicholas Taleb (born 1960) in his book The Black Swan: The Impact of the Highly Improbable (2007): see the quotation. === Pronunciation === (Received Pronunciation) IPA(key): /blæk ˈswɒn/ (General American) IPA(key): /blæk ˈswɑn/ Rhymes: -ɒn === Noun === black swan (plural black swans) Cygnus atratus, a swan with black plumage and a red bill which is endemic to Australia. [from c. 1700] (figurative) Something believed impossible or not to exist, especially if an example is subsequently found; also, something extremely rare; a rara avis. (something extremely rare): Synonyms: rare bird, rarity, unicorn; see also Thesaurus:rarity (specifically, also attributive) A rare and hard-to-predict event with major consequences. ==== Hypernyms ==== (Cygnus atratus): Anatidae – family; Anserinae – subfamily; Cygnus – genus ==== Derived terms ==== black swan event black swan fallacy black swan theory ==== Translations ==== ==== See also ==== tail risk === References === === Further reading === black swan on Wikipedia.Wikipedia black swan theory on Wikipedia.Wikipedia Category:Cygnus atratus on Wikimedia Commons.Wikimedia Commons Cygnus atratus on Wikispecies.Wikispecies