1 definition by WHAT29849

(n) A hand-job where peanut butter is used as a lubricant. When the male ejaculates, the semen (aka "marshmallow fluff") is then mixed with the peanut butter, reminiscent of a fluffernutter sandwich.
I didn't know what she had in mind when she brought out the peanut butter, but then she showed me the "fluffernutter."
by WHAT29849 June 19, 2010
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