Help! I can't find any information on the origin of the idiom/expression: Grease someone's palm. Please help me!

Scroll down to the Online Etymology Dictionary at this site. It explains related uses of "grease" and gives a date for the origin of "grease one's palm."

http://dictionary.reference.com/browse/grease

"grease (someone`s) palm

- to pay a person for something done or given, to bribe someone
We had to grease the palm of the customs agent at the border to get our goods into the country."

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