wife's best friend
Proposed by a contributor, not yet supported by evidence.
Meaning · English
The penis.
Register: slang
Where it’s used:
Used
American English
Examples
Your piece of pork, your wife's best friend, your percy, or your cock.
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).
Common questions
What does “wife's best friend” mean?
The penis.
Is “wife's best friend” formal or informal?
wife's best friend is generally slang.