A (sometimes divided) skirt of a full billowy cut gathered into a narrow hem, supposedly resembling the costume traditionally worn by an inhabitant of a harem; (hence) "harem-skirted" adj.
Origin
Early 20th century; earliest use found in The Irish Times.
Definition of harem skirt in US English:
harem skirt
noun
A (sometimes divided) skirt of a full billowy cut gathered into a narrow hem, supposedly resembling the costume traditionally worn by an inhabitant of a harem; (hence) "harem-skirted" adj.
Origin
Early 20th century; earliest use found in The Irish Times.