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Phrase, to "crack a fat", to get an erection.

Possibly related to the British phrase to "crack one off", to masturbate successfully.

"Crack a fat" is commonly used in Australia.
The teacher wanted me to solve the equation on the blackboard, but I'd cracked a fat (being 15 and all) and was afraid to stand up.
by Frantic November 25, 2003
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