big O
Proposed by a contributor, not yet supported by evidence.
Sense 1
Meaning · English
Orgasm.
Register: slang
Where it’s used:
Used
American English
Examples
Various sections of the brain are activated during the Big O, including the limbic system.
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
Opium.
Register: slang
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “big O” mean?
Orgasm.
Is “big O” formal or informal?
big O is generally slang.