ن ص فn-ṣ-f
(ن) نَصَفَ يَنْصُفُ نَصْفًاnaṣafa yanṣufu naṣfan: to halve, to divide into two equal parts; to reach the half (of something). (This verb is not used in the Quran.)
نِصْفٌniṣf (noun, ism dhāt): half. ﴿وَلَكُمْ نِصْفُ مَا تَرَكَ اَزْوَاجُكُمْ﴾ (An-Nisāʾ 4:12); ﴿نِّصْفَهُۥٓ اَوِ انْقُصْ مِنْهُ قَلِيْلًا﴾ (Al-Muzzammil 73:3)
Form IV (ifʿāl) اَنْصَفَ يُنْصِفُ اِنْصَافًاanṣafa yunṣifu inṣāfan: to do justice, i.e. to treat both parties equally; and this is the origin of the word «inṣāf». (This verb is not used in the Quran.)