420
Proposed by a contributor, not yet supported by evidence.
Also seen as: 4/20 · four-twenty · 4:20 · four twenty
Sense 1
Meaning · English
Cannabis.
Register: slang
Where it’s used:
Used
American English
Examples
Sunday is 420 day, when lovers of marijuana get together to celebrate their fondness for weed.
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Sense 2
Meaning · English
Pertaining to cannabis, its consumption, or cannabis culture.
Register: slang
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Sense 3
Meaning · English
April 20 (abbreviated 4/20 in the US), as an occasion to celebrate cannabis culture.
Register: slang
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “420” mean?
Cannabis.
Is “420” formal or informal?
420 is generally slang.