The Quran

وَالقَواعِدُ مِنَ النِّساءِ اللّاتي لا يَرجونَ نِكاحًا فَلَيسَ عَلَيهِنَّ جُناحٌ أَن يَضَعنَ ثِيابَهُنَّ غَيرَ مُتَبَرِّجاتٍ بِزينَةٍ ۖ وَأَن يَستَعفِفنَ خَيرٌ لَهُنَّ ۗ وَاللَّهُ سَميعٌ عَليمٌ

Muhammad Asad

AND¹ [know that] women advanced in years, who no longer feel any sexual desire,² incur no sin if they discard their [outer] garments, provided they do not aim at a showy display of [their] charms. But [even so,] it is better for them to abstain [from this]: and God is all-hearing, all-knowing.

This conjunction is, I believe, meant to indicate that the verse which it introduces is connected with certain previously revealed passages, namely, verse 31 above and 33:59, both of which allude to the principle of modesty to be observed by Muslim women in the matter of dress: hence, it must be regarded as a separate "section".
Lit., "who do not desire (or "hope for"] sexual intercourse" - the latter evidently being the meaning of nikah in this context. Although this noun, as well as the verb from which it is derived, is almost always used in the Qur'an in the sense of "marriage" or "marrying", there are undoubtedly exceptions from this general rule: for instance, the manner in which the verbal forrn yankihu is used in verse 3 of this surah (see the corresponding note 5 above). These xceptions confirm the view held by some philologists of great renown, e.g., Al-Jawhari or al-Azhari (the latter quoted in the Lisan al-'Arab), to the effect that "in the speech of the Arabs, the original meaning of nikah is sexual intercourse (al-wat')"