The term 420 is used widely in Cannabis culture as a time to get high, a national day to get high, and cannabis itself.

There are a lot of different theories about how the word was first invented:

:: San Rafael theroy ::
In the early 1970's, a group of teenagers who attended San Rafael High School in San Rafael, California used to get high every day at 4:20 in the afternoon under the Louis Pasteur statue.

:: Bob Dylan theroy ::
In Bob Dylan's song, 'Rainy Day Women #12 && 35,' the lyrics contain 'everybody must get stoned.' 420 comes from the title, as 12 * 35 = 420.

:: Highway 420 ::
In Ontario, Canada in the 60's, marijuana grew freely on one of the Highways. This highway was later renamed in 1972 as Highway 420.

:: The Date 4/20 ::
April 20th is coincidentally (or not..) the birthday of Adolf Hitler who was born on April 20, 1889. It is also interesting to note that the Columbine High School shootings also occured on this date in 1999.

There are many other theories that have been debunked such as the Bob Marley theroy and the Police Code theroy.
You: "Yo, dude.. it's April 20th - let's go smoke over there!"
Me: "You also realize that today is Hitler's birthday? Let's go throw some rocks at passing Volkswagen's while smoking mary jane! After all.. hitler invented the VW Beetle"
You: "GOOD IDEA! This is gonna be the best 420 ever!!"
by daavid May 8, 2006
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1)Noun: The time of day for ritual/social smoking of herb. Usually there's enough time to be prepared well to start(inviting friends, driving around, buying stuff, etc).
2)Noun: Herb
" Dude, IT'S ALMOST 420 .. FUCK! Light up right here man."
" This is some high quality 4.2.0.
by redman&kronic January 25, 2009
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who really cares...it's 420 right now!!!
Happy 420!!!!!!!!!!!!! Roll it up Light it up Smoke it up Inhale Ehale
by Junebug April 20, 2004
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420 is april 20 the day to smoke your best bud, or national pot smoking day. It all started with a bunch of teenagers called the Waldos.
stoners mental math 4+20 = 420.... lets go smoke.
by mhorittochelln June 24, 2005
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Code for homicide. From CSI, but is the actual police code used by the Las Vegas Metropolitan Police Department.
419 = Dead Body
419A = Drowned Person
420 = Homicide
420A = Murder/Non-negligent homicide
420B = Manslaughter
420Z = Attempted homicide
421 = Sick or injured
421A = Mentally ill person
422 = Sick or injured Officer



by Alfie The Horndog June 10, 2007
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The national rememberance day to which we all acknowledge that the best joys in life are through the use of killing yourself.
I will smoke that on 420
by Cy O'Hare March 10, 2017
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My dog weighs 420 grammes
by 0b1010101 November 10, 2017
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