an acronym and euphemism for the phrase "Sorry For Partying"
only the "for" is replaced by the numeral 4.
Vin: "You know you spent $30 on fast food last night after the bar right?"
Matt: "S4P"

Vin: "You know you were so drunk at the bar you called it a frat house?"
Matt: "S4P playa"
by DPWM November 30, 2009
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