The abaya "cloak" sometimes also called an aba, is a simple, loose over-garment, essentially a robe

Robe

A robe is a loose-fitting outer garment. A robe is distinguished from a cape or cloak by the fact that it usually has sleeves. The English word robe derives from Middle English robe , borrowed from Old French robe , itself taken from the Frankish word *rouba , and is related to the word rob...

-like dress, worn by some women in parts of the Islamic world including in Turkey, North Africa and the Arabian Peninsula

Arabian Peninsula

The Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...

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Traditional abayat are black and may be either a large square of fabric draped from the shoulders or head or a long caftan. The abaya covers the whole body except the face, feet, and hands.