Floccinaucinihilipilification, the declaration of an item being useless, is the longest non-medical term in the English language.
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In Turkish, the bird we call a Turkey is called "Hindi" ("from India"). In India, it's called "Peru." In Arabic, the bird is called "Greek chicken"; in Greek it's called "French chicken"; and in French it's called "Indian chicken." The bird is indigenous to none of these places.
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Switching letters is called spoonerism. For example, saying "jag of Flapan", instead of "flag of Japan".
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The word "impossible" dropped in use by 50% over the course of the 20th century
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The word 'mile' is derived from the Latin word for 1,000 - the number of paces it took the average Roman!
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