ن ف لn-f-l
(ن) نَفَلَ يَنْفُلُ نَفْلًاnafala yanfulu naflan: to give a gift beyond (what is due); to distribute spoils of war. (This verb is not used in the Quran.)
نَفَلٌnafal pl. اَنْفَالٌanfāl (noun, ism dhāt): spoils of war (which come to hand over and above the original aim); the surah takes its name from it. ﴿يَسْـَٔلُوْنَكَ عَنِ الْاَنْفَالِ﴾ (Al-Anfāl 8:1)
نَافِلَةٌnāfilah (active participle, ism fāʿil, feminine): (1) beyond what is obligatory, supererogatory (2) a child's child, a grandson. ﴿وَمِنَ الَّيْلِ فَتَهَجَّدْ بِهِۦ نَافِلَةً لَّكَ﴾ (Al-Isrāʾ 17:79); ﴿وَوَهَبْنَا لَهُۥٓ اِسْحٰقَ وَيَعْقُوْبَ نَافِلَةً﴾ (Al-Anbiyāʾ 21:72)