Why are toilets called johns?

Why are toilets called johns? Very simple question . . . probably simple answer as well, but I’ve asked Cecil several times now with no response.

I heard that the toilet was invented by a guy named Thomas Crapper. Hence use the crapper, take a crap, etc. Dubious way to be remembered if you ask me.

…Just looked it up…

This site says the word ‘crap’ may have a different origin.

http://www.plumbingstore.com/psthomas.html

Also found this:

Source: http://www.toiletology.com/history.shtml

No idea if that John has anything to do with the name.

Scary how much stuff can be found searchingthe internet on toilets though!

You’re gonna love this one. . .

http://castle.uvic.ca/shakespeare/Library/SLTnoframes/intellectual/watercloset.html

Even though Thomas Crapper invented the modern toilet, the original idea was proposed by Sir John Harington in a book whose title “is a pun on ‘a-jacques,’ or what is still called a ‘john’.”

missed it by two minutes. . .

Cecil Adams on Why do we call it a “john?”

The Dictionary of Obscenity & Taboo says John may be a euphemism of Jakes, as Jeff_42 suggested.

Crapper is probably from crap a word much older than the Thomas Crapper story. The word orignially meant chaff, then rubbish, then feces. Urbanlegends.com says

Cecil weighs in on the controversy here

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