The coat a Muslim woman chooses should be suitable for wearing over an abaya. This means it should be loose-fitting so the abaya doesn't constrict under a coat. And it should definitely take both class and modesty into account.
The coat a Muslim woman chooses should be suitable for wearing over an abaya. This means it should be loose-fitting so the abaya doesn't constrict under a coat. And it should definitely take both class and modesty into account.