خ م سkh-m-s
— This root occurs 8 times in the Quran, only in numeral forms.
خَمْسkhams / خَمْسَةkhamsah: the number five. ﴿وَيَقُوْلُوْنَ خَمْسَةٌ سَادِسُهُمْ كَلْبُهُمْ﴾ (Al-Kahf 18:22)
خَمْسُوْنkhamsūn: fifty. ﴿فِيْ يَوْمٍ كَانَ مِقْدَارُهُۥ خَمْسِيْنَ اَلْفَ سَنَةٍ﴾ (Al-Maʿārij 70:4)
خُمُسkhumus: a fifth part. ﴿فَاَنَّ لِلّٰهِ خُمُسَهُۥ﴾ (Al-Anfāl 8:41)
خَامِسkhāmis / خَامِسَةkhāmisah: fifth. ﴿وَالْخَامِسَةُ اَنَّ لَعْنَتَ اللّٰهِ عَلَيْهِ﴾ (An-Nūr 24:7)