Adynaton is a figure of speech in the form of hyperbole taken to such extreme lengths as to insinuate a complete impossibility:
"I will sooner have a beard grow in the palm of my hand than he shall get one on his cheek."
The word derives from the Greek ἀδύνατον, neuter of ἀδύνατος, "unable, impossible".
Classical and medieval usage
Adynaton was a widespread literary and rhetorical device during the Classical Period. In the Eclogue of Plutarch, there is a long list of proverbs and the first section is titled ΠΕΡΙ ΤΩΝ ΑΔΥΝΑΤΩΝ, consisting of proverbs that are built on adynaton. The adynaton form was often used for vows and covenants, such as in the 16thEpode of Horace, 25-34. Its plural form was translated in Latin as impossibilia. A frequent usage was to refer to one highly unlikely event occurring sooner than another: Zenobius's collection of proverbial expressions includes "to count sand" to characterize something impossible or unattainable. However it largely fell into disuse during the Middle Ages before undergoing a minor revival in the works of romantic poets, who would boast of the power of their love, and how it could never end.
Adynata are sometimes used within works of fiction or drama: Impossible tasks appear often in legends and folklore, and can form elements of ballads, riddles and proverbs. Examples include: the tale of "The Spinning-Woman by the Spring",
Modern usage
Some modern adynata include:
In Bulgarian: когато цъфнат налъмите and когато върбата роди круши. koga se pokači svinja s z´´lti čehli na krusa ; from a poem by Gerrit Komrij: "Eer maakt men lakens wit met inkt dan dat ik zeg wat ik thans lijden moet". "Op St. Juttemis"
In English: When pigs fly!, and Not before Hell freezes over! and its derivative . When the moon turns to green cheese.
in Finnish: kun lehmät lentävät or kun lipputanko kukkii
In French: Quand les poules auront des dents, La semaine des quatre jeudis . "À la St. Glinglin" ; "Aux calendes grecques"
In German: Wenn Schweine fliegen könnten ; Wenn Ostern und Weihnachten zusammenfallen
In Slovak: keď budú padať traktory or na svätého dindi
In Spanish: Cuando las vacas vuelen, instead of "las vacas" the words "los chanchos" are also used, replacing "the cows" with "the pigs" or, in Spain there could also be used Cuando las ranas críen pelo
in Swedish: två torsdagar i veckan. It is also said as "two Sundays in the same week", but other weekdays are rarely used.
