A woman may not have a "man's haircut".
This Halacha is location-specific; the norm of the place you are in, defines what is "masculine".
Applies to women, always, everywhere.
Verse: "A woman should not wear man's clothing" (Devarim 22:5)
Source: The Chafetz-Chaim's Sefer haMitzvot haKatzar; Prohibition 178
Tuesday, 18 Marcheshvan 5771
Rivka bat Tirtzel.
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