First, there is no police code "420". There are no police codes referring to any particular drug, marijuana included. It's time to bury this myth.

4:20 was the designated time for a small group of smokers at San Rafael High School in California to meet at a specific location and light up. The number originates some time around 1971. It has since been adopted by smokers the world over as the "universal time to get high."
by This is my name. June 6, 2005
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The "official time" to smoke it up...
The original story:
A small group of kids in high school used to meet up everyday after school at 4:20 and smoke on the hill. One day on April 20th, at 4:20 they were all like "'s 4:20, and 4/20- we should make this celebration official" the celebration spread and now 4/20 is an amazing day to get blazed thanks to a group of high school kids from norcal from the 70's's 4/20...let's get blazed
by marinite June 17, 2005
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1. The time to get high as adopted by marijuana culture.
2. A way of mentioning marijuana in the presence of authority figures so as not to get caught.
Perhaps the most compelling source of 4:20 is the time of day an H.P. Lovecraft character cites for having become sober after succumbing to the intoxication of a "mirage-plant":

"I had encountered at least one of those curious mirage-plants about which so many of our men told stories. Anderson had warned me of them, and described their appearance very closely—the shaggy stalk, the spiky leaves, and the mottled blossoms whose gaseous dream-breeding exhalations penetrate every existing make of mask...Although everything was spinning perilously, I tried to start in the right direction and hack my way ahead. My route must have been far from straight, for it seemed hours before I was free of the mirage-plant's pervasive influence. Gradually the dancing lights began to disappear, and the shimmering spectral scenery began to assume the aspect of solidity. When I did get wholly clear I looked at my watch and was astonished to find that the time was only 4:20. Though eternities had seemed to pass, the whole experience could have consumed little more than a half-hour."
by brap May 30, 2005
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4:20 originated in San Rafael. What happened was, a group of guys who went to San Rafael High School in 1971 would smoke weed at the Louis Pasteur statue at San Rafael High School, and every time they did this they would do it at 4:20 PM. They would later come up with the term "Louis 4:20" to use when on the phone around their parents or near authoritative figures. It would later become a world wide phenomenon (how it did is beyond me) were stoners would smoke up on April 20 (4/20) at 4:20 AM/PM (depends on how early you wake up). Lastly, 4:20 is not a police code for pot or any other drug.
"Dude, let's get blazed at 4:20 AM and PM man!"
"Alright man! Wait. How the fuck are we gonna make up that early?"
"Oh shit. Fuck. Uhhhhhhhhhhhh. Shit. Oh! I got it! I'll set an alarm!"
"Dude, that's some fuckin' Einstein shit right there bro!"
by dazedandblazed415 December 22, 2008
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The universally accepted time to smoke marijuana. Began when a group of high schoolers in the '70s from San Raphael High School in California decided to meet up every day at 4:20 to smoke.
"They had just bough a sack weighing 3.5.
It was 4:19, just about that time. i.e., almost 4:20
They pulled out the binger and I started to drool.
It was the five-foot caustic weapon crystal, too.
I caught the fumes and I lost my mind,
Happens every time that I smoke the kind."
-Wasting Time, by ALO
by OneTimeOnly January 10, 2007
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International Smokers Holiday, celebrated on the fourth month twentieth day on the fourth hour and twentieth minute p.m. (also a minor daily tradition to smoke at 4:20 p.m. tradition started by a group of students in california that used to meet at a certain place at this time after class daily. (normally marijauna), 4:20 was a code word so teachers and administration would not catch on to their activities.
are you down for 4:20? sure!
by Thomas Watkins January 24, 2008
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On April 20th all the potheads around the world light up and get baked at 4:20 pm.
"Yo dawg it's 4:20. Lets get a 50 bag and get fuckin jacked."
by Camdizzle September 30, 2004
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