Sahra Abaya

وَقُل لِّلْمُؤْمِنَـٰتِ يَغْضُضْنَ مِنْ أَبْصَـٰرِهِنَّ وَيَحْفَظْنَ فُرُوجَهُنَّ وَلَا يُبْدِينَ زِينَتَهُنَّ إِلَّا مَا ظَهَرَ مِنْهَا ۖ وَلْيَضْرِبْنَ بِخُمُرِهِنَّ عَلَىٰ جُيُوبِهِنَّ ۖ وَلَا يُبْدِينَ زِينَتَهُنَّ

And tell the believing women to lower their gaze and guard their chastity, and not to reveal their adornments  except what normally appears. Let them draw their veils over their chests, and not reveal their hidden adornments.

Quran 24:31