1 definition by Bartender Bill

The act of putting on protection before sex, such as a condom.

Derived from "buckle up", which is the act of securing safety straps before driving a car.
"Baby I'm gonna plow you like a foot of snow."
"Don't forget to fuckle up first!"
"Of course - it's the law"
by Bartender Bill August 24, 2016
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