Named for Reverend William Archibald Spooner. Spooner was best known for mixing up consonant sounds at the beginning of words. Such as ‘Is the bean dizzy?’ that should be ‘Is the dean busy?’ These unintentional quips of humor are now a days a means of cursing without cursing.
I am not endorsing cursing, but have fun with it. If you have a verbal flub, laugh it off. Apparently even the queen had her share of spoonerisms. (see link below)