spoonerism \SPOO-nuh-riz-uhm\, noun:
The transposition of usually initial sounds in a pair of words.

Some examples:
* We all know what it is to have a half-warmed fish ["half-formed wish"] inside us.
* The Lord is a shoving leopard ["loving shepherd"].
* It is kisstomary to cuss ["customary to kiss"] the bride.
* Is the bean dizzy ["dean busy"]?
* When the boys come back from France, we'll have the hags flung out ["flags hung out"]!
* Let me sew you to your sheet ["show you to your seat"].
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Spoonerism comes from the name of the Rev. William Archibald Spooner (1844-1930), a kindly but nervous Anglican clergyman and educationalist. All the above examples were committed by (or attributed to) him.