Slang. The shortening of local county zip codes to only double-digit zips to disclose one's location or intention to be in a location at a later time.
Ex. Clive used a double-digit zip to disclose his location later in the day rather than using all five numbers of "42962" and "42939":

"Yo, I be in the 6-2 later to get dat job done for ya".

"Where ya at?" "In the 3-9 hittin' the ATM for da shizzle"
by ImperialSaint33 June 10, 2013
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