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A complex sexual procedure that involves 21 men and 1 woman. It goes as follows:
2 cocks in the ass
2 cocks in the pussy
2 cocks between the titties
2 cocks in the mouth
1 cock in each ear
1 cock in each eye socket
1 cock in each nostril
1 cock in each hand
1 cock in each foot
1 cock in each armpit
and finally...1 cock in the navel(belly button)
Count em all up...and thats 21 cocks. Blackjack is probabaly physically impossible, but its worth a try if you and your 20 buddies are bored one day and wanna try it out on some sick twisted bitch.
Sophie gathered 21 guys and recorded the first successful blackjack in history!
by Nilknarf Den January 17, 2006
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The only game worth playing in a casino. In all the other games, the house has a bigger advantage. Some people use a method called card counting to know when to bet high and when to bet low.
Also, the combination of 2 cards equaling 21 in the game.
by Ed April 05, 2005
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9
Actually the low house advantage comes from knowing the precise mathematical combinations of the cards. If you don't know them, you might as well be wasting your money.
Blackjack is not as easy as AYB is trying to say it is.
by Jared November 02, 2003
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10
a weapon used to crack people's skulls open
Ex:Fishing weight on the end of a large spring
I cracked his head open with a black jack.
by The Fonz985 November 05, 2005
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11
A card game held commonplace within casinos worldwide in which the goal is to get as close to 21 as possible without going over to beat the dealer and make the money you bet back as well as an equal amount from the casino. Each person is dealt two cards and has the decision to either hit(get a new card) stay(stay at current value) double(double your bet and recieve one card) or split(if two cards form a pair one can split them into two hands)If your two cards recieved are an ace and a ten (10,jack,queen,king) then you have a blackjack and are paid 3:2 on the hand.
I doubled my bet when i hand a 10 and got 20 but the dealer flipped over a Black Jack and i lost all my money.
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12
An amount of marijuana, consisting of 21 grams or 3/4 of an ounce. Can run anywhere from up at 200-240, when dealing on face value, being swindled or if for good product, down to 140 or 150, usually a hookup or for skank weed.

A blackjack is extremely uncommon in the drug market. A blackjack is usually sold as a favour from the seller, or under similar extraordinary circumstances.

The name blackjack can also refer to when a person sells 14 grams of a skanky blackjack at face value. Thereby sucker punching someone, leaving the seller with a free quarter-ounce.
My buddy's 21st birthday is this weekend. I'm thinking I'm gonna need more than a half-O, but I can't afford a full ounce. Hopefully, I can get a blackjack and my roommate will buy out the rest.

This weed ain't that good, but i got it free from blackjackin' those freshmen jocks.

by Phantom of the Night April 18, 2007
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A word describing someone (usually a female) who is aged 15, as you are unsure wether you can have sex with them.
"she was 15" "as in blackjack?" "yeah" "not sure wether you can hit it?" "exactly"
by wildbill56 March 10, 2010
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