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.

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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

Early trading suggests a 58 point gain for the S&P 500, with the Dow Jones Industrial Average priced for a 420 point advance and the tech-focused Nasdaq looking at a 260 point bump.

From Barron's • Mar. 25, 2026

After that, stocks dropped to 420 in late October, followed by a rally that smashed through 600 for the first time in 1959 and quickly rallied toward 700.

From The Wall Street Journal • Mar. 7, 2026

In a 420 word-long post on X, OpenAI CEO Sam Altman hit back, calling Anthropic "dishonest" and "deceptive" - and even accusing the firm of using "doublespeak".

From BBC • Feb. 5, 2026

Demand for gold was the biggest ever for a fourth quarter, reaching 1.303 tons, boosted by ETF inflows and a 12-year high for bar- and coin-buying of 420 tons — a 30% annual gain.

From MarketWatch • Jan. 29, 2026

In his comic play The Clouds, Aristophanes, writing in 420 bc, lampooned rhetoric as the art of weak reasoning, “which by false arguments triumphs over the strong.”

From "Words Like Loaded Pistols" by Sam Leith