A spoonerism is an error in speech or deliberate play on words in which corresponding consonants, vowels, or morphemes are switched (see metathesis). It is named after the Reverend William Archibald Spooner (1844–1930), Warden of New College, Oxford, who was notoriously prone to this tendency. A spoonerism is also known as a marrowsky, after a Polish count who suffered from the same impediment. While spoonerisms are commonly heard as slips of the tongue resulting from unintentionally getting one's words in a tangle, they can also be used intentionally as a play on words. In some cultures, spoonerisms are used as a rhyme form in poetry, such as German Schüttelreime. In French, "contrepèterie" is a national sport, the subject of entire books and a weekly section of Le Canard enchaîné. Spoonerisms are commonly used intentionally in humour.

Most of the quotations attributed to Spooner are apocryphal; The Oxford Dictionary of Quotations (3rd edition, 1979) lists only one substantiated spoonerism: "The weight of rages will press hard upon the employer" (instead of "rate of wages"). Spooner claimed that "The Kinquering Congs Their Titles Take" (in reference to a hymn) was his sole spoonerism. Most spoonerisms were probably never uttered by William Spooner himself, but rather made up by colleagues and students as a pastime.Richard Lederer, calling "Kinkering Kongs their Titles Take" (with an alternative spelling) one of the "few" authenticated Spoonerisms, dates it to 1879, and gives nine examples "attributed to Spooner, most of them spuriously". They are: