Switching letters is called spoonerism. For example, saying "jag of Flapan", instead of "flag of Japan".
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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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Anuptaphobia is the fear of staying single.
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The word "listen" contains the same letters as "silent."
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Stressed is Desserts spelled backwards.
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The word "impossible" dropped in use by 50% over the course of the 20th century
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