Mumpsimus

The term originates from an apocryphal story about a poorly educated Catholic priest saying Latin mass who, in reciting the postcommunion prayer Quod ore sumpsimus, Domine (meaning: 'What we have received in the mouth, Lord'), substitutes the non-word mumpsimus, perhaps as a mondegreen.

He said that the men whom Cardinal Wolsey had asked to find reasons why Catherine of Aragon was not truly the wife of King Henry VIII of England were "all lawyers, and other doctors, mumpsimuses of divinity".

[4] Garner's Modern English Usage notes that the word could describe George W. Bush because of his persistent habit of pronouncing "nuclear" as "nucular", despite the error being widely reported.

[15] In his speech at the State Opening of Parliament on Christmas Eve 1545, Henry VIII said:[16] I see and hear daily, that you of the clergy preach one against another, teach, one contrary to another, inveigh one against another, without charity or discretion.

"[17] In an 1883 polemic on errors in translations of the Christian Bible, John Burgon says, "If men prefer their 'mumpsimus' to our 'sumpsimus', let them by all means have it: but pray let them keep their rubbish to themselves—and at least leave our SAVIOUR's words alone.

The Renaissance humanist scholar Desiderius Erasmus of Rotterdam may have coined the word.
William Tyndale may have been the first to use the word in an English-language book.