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420

American  
[fawr-twen-tee, fohr‐] / ˈfɔrˈtwɛn ti, ˈfoʊr‐ /
Or 4:20 or 4/20

noun

Slang
  1. marijuana.

    Are you carrying any 420 on you?

  2. marijuana drug use: The guys at the party were all 420-friendly.

    Police presence at the concert discouraged 420.

    The guys at the party were all 420-friendly.

  3. the twentieth day of the fourth month, or the time 4:20, when referenced as a day or time for cannabis consumption or the celebration of marijuana culture.

    The head shop has a big pipe sale every year on 420.


Usage

What is 420? 420 is a slang term (or a kind of code word) referring to marijuana or marijuana use. Due to this association, 420 is also used as the name of an unofficial holiday that marijuana enthusiasts celebrate by using marijuana. It is sometimes called Weed Day (weed is a slang term for marijuana).

Etymology

Origin of 420

First recorded in 1970–75; a code word derived from the meeting time of a particular group of marijuana smokers in 1971, later popularized by fans of the band the Grateful Dead

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Men can get breast cancer too, with about 420 new cases every year in the UK.

From BBC Aug. 4, 2026

A couple of laps in the eager and edgy 420 Sport made me realize how long it had been since I actually had fun—that’s the word!—in a sports car.

From The Wall Street Journal Jul. 25, 2026

Heal, who thinks England will win on penalties, said staff would prepare enough seats and food for all 420 students - but "realistically" only expects half to turn up.

From BBC Jul. 2, 2026

The moves have left the pair, which are not profitable yet, trading at roughly 120 times and 420 times trailing sales.

From Barron's May 28, 2026

Each one stood 420 feet tall, the equivalent of a thirty-story skyscraper, and had three whirring blades.

From "Killers of the Flower Moon" by David Grann

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