a). {x e N : 19 < x < 21 }.

b). set theory. The cardinality of a set containing twenty objects.

c). The number of years you spend in jail for assault with a deadly weapon.

d). The age which is slightly less worthless than 19, and slightly more worthless than 18. The age at which you are considered to be well into fully legal adulthood, yet the government still deems it necessary to babysit certain aspects of your life. Despite the notoriety of turning a new decade, turning 20 doesn't mean a damn thing.
Last night, bobby smoked exactly twice as many joints as he could count on both of his hands. How many joints did bobby smoke?

Answer: 20
by General Septem October 03, 2009
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Marijuana (or) weed, usually smoked with a pipe or bong. (Word taken from movie 'Friday')
"I got that 20 20 for friday night" - Jason
"ohh yeah. We goin fo' 20 20!! Niiiiiigga!!" - Jack
by Jack Sprack October 15, 2008
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Ghetto Juice. I.E. Banana Red, Red Grape, or the all new "Bling Bling Blue Raspberry".
My nigga, get down to the corner store and get me some 20/20.
by Russ November 19, 2003
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Location.

Derived from the lingo of CB radio users
Gimme a radio check willya oh and what's yer 20?
by Dirge October 30, 2004
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a stand ability acquired by Joe 🅱iden that allows him to

go to different dimensions and even bring back alternate joes
Jojo Biden: $20 IS $20 *goes into alternate world
by President Valentine February 24, 2021
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"haven't seen chris baeher in a while..." "dude didn't you hear? he's back in 20/20"
by lauren September 01, 2003
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Refering to a $20.00 bag of marijuana.
Also known as a "twin"
by Chron December 26, 2002
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