What does 420 mean? Inside the treasure hunt that launched April 20 marijuana 'holiday'

At 4:20 p.m. on any given day, there's a marijuana user somewhere across the globe, chuckling at the clock while lighting up a joint or packing in a glass pipe.

The number 420 has become a secret code among potential roommates and people on dating websites, a way to covertly let someone know that they welcome marijuana into their home or lovelife.

And April 20 — 4/20 — has become the unofficial stoner holiday, with marijuana legalization activists gathering from New Jersey to California and lighting up in protest.

For decades, the number "420" has been as big a part of cannabis culture as Cheech and Chong or the image of a green pot leaf.

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“We’ve already gotten to the point where you have corporate companies tweeting about 420 and other advertisements. It’s gone that far,” said David Bienenstock, a cannabis journalist and author. “It’s really transformed into this day of public celebration and a holiday for the cannabis community, which is actually a really important thing.

"Every culture and community needs that day of celebration, of being really visible – particularly a culture that has faced the oppression that weed smokers have faced," Bienenstock said.

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But as legal weed becomes closer to a reality in New Jersey, many novices remain unaware: What does 420 mean? Where did 420 come from?

Before we get into the history, let's debunk some of the myths surrounding 420:

Police use the radio code "420" to report a marijuana smoking in progress

This is the most popular myth surrounding 420 but it's just that: A myth. While there are some standards, police codes differ by state, county and local department and not all of them use code no. 420.

In Las Vegas, police officers use 420 to call in a homicide. In San Francisco, it's a juvenile disturbance.

Many New Jersey police departments, including the State Police, don't even use code no. 420.

While there may be a few police dispatchers in the United States who get a laugh out of assigning marijuana offenses to code no. 420, they're the exception to the rule.

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“But it’s entirely understandable that our community would want to … sort of transform this tool of our oppression at the hands of the police by taking over 420 and changing the meaning,” explained Bienenstock on the latest episode of the Great Moments in Weed History podcast.

But it's still just a myth.

There are 420 chemicals in marijuana

Nope.

Most studies have determined that there are more than 500 compounds in a cannabis plant, though the number and type vary by strain.

There are over 100 cannabinoids, the chemicals most often studied in order to determine the physical and mental effects of marijuana.

April 20 is Hitler's birthday

"Put on your tin foil hat, because we're going deep into how Nazis started 420," Bienenstock joked on his podcast.

"That would be such a bummer for the entire world," replied co-host Abdullah Saeed.

April 20 is also Chinese Language Day, Star Trek actor George Takei's birthday and the start of the Spanish-American War.

The mass shooting at Columbine High School in Littleton, Colorado, occurred on April 20, 1999, but there are conflicting reports about the date choice: Some claim that the shooters were Nazi sympathizers and planned for the shooting to fall on Hitler's birthday. Others say it was simply a coincidence.

But the number "420" was associated with marijuana long before the Columbine tragedy.

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So then what's the real story?

The legend begins in the mythical land of Northern California: Once upon a time, there were five friends, smoking weed and sitting on top of a wall at San Rafael High School. The other students called them "Waldos."

"We were just friendly, happy, funny guys. And somehow because of that, all these doors opened up for us all the time," said "Waldo Steve" Capper in an interview with the Reno Journal-Gazette.

Check out the history of 420 from the stoners who invented the term!

In the fall of 1971, the Waldos soon heard of a hidden patch of cannabis, abandoned by a U.S. Coast Guardsman stationed nearby who was afraid he'd get busted.

They decided to meet up at the school's statue of Louis Pasteur (who completed the first pasteurization test on April 20, 1862) to get high and go on a weed treasure hunt. But they had to wait until after their various sports team practices and settled on a specific time: 4:20 p.m.

They used the phrase "4:20 Louie" to remind each other of their plans, eventually shortening it to simply "4:20."

The phrase quickly grew beyond a reference to their futile search for the secret garden of weed. Instead, it was used as a covert way to talk about marijuana — who was selling it, who wanted to buy it and who was already — right under the nose of teachers, parents and police officers

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"I could walk up to the Waldos, and I'd go, '420,' and it was like mental telepathy. They would know if I was saying, 'Are you stoned? Do I look stoned? Do you have any? Do you want to go off and get stoned?'," Capper said. "You could say ten different things by saying 420 and it was just mutually understood all the time."

So five hippies from California came up with '420'?

That's right. But you can thank the Grateful Dead for making it a commonplace term.

Yes, that Grateful Dead.

The band had recently relocated to San Rafael, and the Waldos had various connections: One of the kids' older brothers was a manager for bassist Phil Lesh's side project. Another one's father purchased real estate for them. They watched their dogs, were welcomed into their parties and Reddix even got a gig as a roadie for the band.

The band picked up on the "4:20" habit and, soon after, so did the "Deadheads," well known for their particular interest in smoking weed before, during and after shows.

Nearly 20 years later, the phrase would get national attention after High Times magazine published a flyer that explained the "code." And it called for all marijuana users to meet at a Marin County overlook and light up a joint at 4:20 p.m. on April 20.

"There's something magical about getting ripped at 4:20, when you know your brothers and sisters all over the country and even the planet are lighting up and toking up right along with you," the flyer read.

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"Now there’s something more grand than getting stoned at 4:20. Now we are talking about the day of celebration, the real time to get stoned, the grandmaster of all holidays, 4/20 or April 20. This is when you must get the day off work or school," it continues.

The first ever 420 — April 20 — celebration was born.

There's no way this is true.

Not only is the 420 story true, there's proof!

The Waldos' website has multiple examples of how the number was an inside joke among their friends and at San Rafael High School. There are postmarked letters — to each other, to friends and to members of the Grateful Dead — that make reference to the code. There's a tie-dye flag with "420" made in their art class. There's a school newspaper, with a student simply stating "420" when asked what he'd say in front of his class.

And in 2016, the Waldos tracked down retired U.S. Coast Guardsman Gary Newman — more than 40 years after his time in San Rafael. He confirmed drawing up the "treasure map" that sparked the 420 legend.

"We never thought pot would be legal when we were kids," Reddix said. "You had to do everything underground because we were criminals, outlaws."

Mike Davis; @byMikeDavis: 732-643-4223; mdavis@gannettnj.com