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1.
Girls who live in Jersey, the Bronx, Queens, Brooklyn or worse Long Island who go into Manhattan on the weekend for clubbing. The term primarily refers to girls from Jersey or LI.

Bridge and Tunnel because that is their mode of transportation into/out of the island. Posse because they frequently travel in large packs.
Jenny's ripped jeans and Springsteen t-shirt gave her away as a member of the Bridge and Tunnel posse.
by Lou Stenspayce December 24, 2003