What is Sex Money?
1.
n. the money (usu. borrowed from a friend) a girl brings with her on a date with a guy when she is not sure whether or not he will pay
origin It originated in southern New Mexico because if all goes well she'll have sex with the money in her pocket.
"Hey, I'm going on a date tonight but I don't know if he'll pay. Can I borrow some sex money?"
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