24 : 60
وَٱلۡقَوَٰعِدُ مِنَ ٱلنِّسَآءِ ٱلَّٰتِي لَا يَرۡجُونَ نِكَاحٗا فَلَيۡسَ عَلَيۡهِنَّ جُنَاحٌ أَن يَضَعۡنَ ثِيَابَهُنَّ غَيۡرَ مُتَبَرِّجَٰتِۭ بِزِينَةٖۖ وَأَن يَسۡتَعۡفِفۡنَ خَيۡرٞ لَّهُنَّۗ وَٱللَّهُ سَمِيعٌ عَلِيمٞ
As for elderly women who have no interest in marriage, there is no blame on them if they take off their outer garments without revealing their beauty. But if they modestly refrain from it, that is better for them. And Allah is All-Hearing, All-Knowing.