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What Does 420 Mean & Why is it Associated with Marijuana?

cannabis leaf in front of 420

Whether or not you’re a part of the cannabis community, you’ve likely heard the term “420.” There’s no doubt that the number 420 has a strong connection to marijuana, but what does 420 mean? 

There are a few different origin stories about the number 420, but the fact remains: 420 is recognized everywhere as the time to consume cannabis. Whether you’re talking about 4:20 PM or April 20th, anything that involves 420 is a common reason for people to gather together and enjoy cannabis.

If you want to know more about 420, our article will cover:

  • Where Did the Term 420 Come From?
  • What are the Myths Around 420?
  • How Did the Number '420' Become so Famous?


Where Did the Term ‘420’ Come From?

Anyone who’s researched why 420 is so special knows there are a few different stories about the origin of the number. Some people say 420 comes from a Bob Dylan song, while others believe it’s because there are 420 chemicals in cannabis. The truth is, the most likely origin of 420 begins with a group of students and The Grateful Dead.

Back in 1971, a group of students who called themselves The Waldos would congregate during school to consume cannabis. One day, a fellow student presented them with a treasure map to his brother-in-law’s marijuana garden growing illegally in the forest on Point Reyes Peninsula. The Waldos decided to meet after school and drive to Point Reyes, but since school got out at 3:10 pm, and some of the Waldos had after-school activities lasting an hour, they chose to meet at precisely 4:20 pm at the Louis Pasteur statue.

After school, they would try to find the patch. It eluded them, but after tossing around the phrase 420 all day, the number permanently entered their lexicon, and they began using it in everyday speech to covertly discuss getting high without tipping off parents or teachers.

What Are the Myths Around 420?

You’ve probably heard the myth that ‘420’ is a police code used by officers when someone is smoking marijuana in public. However, this is false. And there are many more myths about where 420 came from. Here are a few of the most common: 

  • The California penal code for cannabis offenses is ‘420’ (Fact: it’s Code 11357 HS.)
  • There are 420 chemicals found in a cannabis plant. (Fact: there are likely many more.)
  • The Grateful Dead invented 420. (Fact: now you know that it was a group of students.)
  • Bob Marley died on April 20. (Fact: Bob Marley died on May 11.)
  • 4:20 PM is tea time in Amsterdam. (Fact: that’s just not true.)

How Did the Number 420 Become so Famous?

You might be wondering, how did one group of students make the number 420 famous? Actually, The Grateful Dead played an important role in the term making the leap from The Waldos to the rest of the world.

The Waldos had connections to the band and became good friends with some of the members. When band members and the audience heard The Waldos using the term 420, it caught on and took on its own life from there. The number has become so popular, in fact, that Colorado transportation officials had to remove the ‘420’ mile marker on Interstate 70 because it kept getting stolen. It was replaced with mile marker 419.99.

And there you have it. What began as five students with a pot treasure map has blossomed into an international celebration of and a rallying cry for the cannabis community.


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