A narrow hem drawing in the material of a garment, which billows over it, creating an effect likened to that found in the costume traditionally worn by an inhabitant of a harem.
Origin
1920s; earliest use found in The New York Times.
Definition of harem hem in US English:
harem hem
noun
A narrow hem drawing in the material of a garment, which billows over it, creating an effect likened to that found in the costume traditionally worn by an inhabitant of a harem.