Negative Commandment #178
Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos)
By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
178. It is a negative commandment "a woman may not wear a man's garment"
As it states in Devarim (Deuteronomy) 22:5, "The garment of a man should not be on a woman." This means a woman is not to wear clothing or jewelry that is known in the city to be for a man. A woman also should not cut her hair to be like a man's.
This applies in all places and at all times.