A Spoonerism is a play on words in which corresponding consonants or vowels are switched, named after the Reverend William Archibald Spooner (1844–1930), Warden of New College, Oxford, who was notoriously prone to this tendency. Some of his famous (and possibly apocryphal) quotes from the chapel include "The Lord is a shoving leopard," "It is kisstomary to cuss the bride," and "Mardon me padam, this pie is occupewed. Can I sew you to another sheet?." (Pardon me, madam, this pew is occupied. Can I show you to another seat?) The spoonerism is a now legendary 'slip of the tongue.'
Other gaffes worth mentioning are his angry speech to a student, "You have hissed all my mystery lectures, and were caught fighting a liar in the quad. Having tasted two worms, you will leave by the next town drain," actually intending to say missed history, lighting fire, wasted terms, and down train, respectively. A few more which you can probably work out for yourself include "We must drink a toast to the queer old Dean", "We'll have the hags flung out", "a half-warmed fish" and "Is the bean dizzy?"