furphy?

[David Bergdahl]

In an article on Tom Lehrer on www.smh.com.au/articles/2003/02/28/1046407753895.html 
the word "furphy" appears:

>The widespread rumour that von Braun sued Lehrer proves to be a furphy. "I've heard that a lot, that I have to pay all my royalties for the song to him and so on and so forth. No, that's one of those myths. There is no possible way he could have sued me."

Merriam-Webster Online doesn't have a cite.  It looks like it's formed on "murphy"...