When walking up the stairs at school and the person in front of you has a huge backpack and it smacks you in the face. Another way you can endure pack smack is when someone turns suddenly in the hallway, their backpack hits you, thus pushing you over.
Joni just pack smacked me right into those lockers.

Man, That Josh kid totally pack smacked me in the face today.
by plasticbeach November 2, 2010
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The pack of ten hypodermic needles sold at pharmacies to people without a prescription. Intended for use by diabetics without a prescription in an emergency, but more often used by heroin ("smack") junkies and vagrants.
ex. 1— Hey, Alex just scored a balloon, lets grab a smack pack and chase the dragon.

ex. 2— Billy and I are going to lunch but he forgot his insulin syringes at home so we need to grab a smack pack from Duane Reade
by xreal February 6, 2015
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When a new guy walks into a gym whos untoned and weak, and a big 6pack bencher smacks him on the belly like hes sticking an expected expiry date sticker on a card board box.
Big weight lifter: >Smack< oi oi get on the tread mill outa way good lad big boys are in the building, stick at it and yal be lifting 16 stone and 3 pounds of that meat your eyeing up you know the one, shell get you revved if you break down. PUMP SOME BLASTARD SHELLS AND DOWN SOME HERCULES POWder!!
Flat pack smacked wimpy dog squert: >gulp<
by Step lupid July 12, 2023
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