Mustache vs. Moustache
“Mustache” and “moustache” are regional spellings of the same word for hair above the upper lip. The guide keeps the documented US/UK preference explicit.
Use “mustache” in US spelling and “moustache” in mainly UK spelling.
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| US spelling | mustache | Use the US form when that regional style governs. |
| mainly UK spelling | moustache | Use the mainly UK form when that regional style governs. |
| mixed-document editing | one consistent regional or house style | Do not alternate spellings without a reason. |
Quick tests
Meaning / construction test
Is the document following US spelling conventions?
If yes: Use “mustache.”
If no: For a mainly UK spelling context, use “moustache”; otherwise follow the chosen house style.
Caveat: The forms name the same thing; the difference documented here is regional spelling rather than meaning.
Examples
He trimmed his mustache before the photograph.
The spelling follows US usage.
He trimmed his moustache before the photograph.
The spelling follows mainly UK usage.
The style sheet specifies “moustache” throughout the edition.
A house style can settle the variant consistently.
Further guidance
Core difference
Use “mustache” in US spelling and “moustache” in mainly UK spelling.
Style Boundary
Choose the form that matches the regional or house style of the document, and keep the choice consistent where both forms are acceptable.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Mustache — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Mustache as US spelling and moustache as mainly UK spelling