snollygoster \SNOL-ee-gos-ter\, noun:
Slang. a clever, unscrupulous person.
A snollygoster is a shyster, and not, as President Truman thought, a man born out of wedlock…
-- Anthony Burgess, Homage to "Qwert Yuiop," 1986
"...But you wouldn't be advised, would you, you chuckleheaded old snollygoster!"
-- William Kelley, "The Tyree," 1979
This American English slang term, which entered English in the mid-1800s, is of unknown origin.
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