• أَثْخَنتُمُوهُمْ
• يُثْخِنَ

Appears 2 times in the Quran.

1. 8:67 مَا كَانَ لِنَبِىٍّ أَن يَكُونَ لَهُۥٓ أَسْرَىٰ حَتَّىٰ يُثْخِنَ فِى ٱلْأَرْضِ تُرِيدُونَ عَرَضَ ٱلدُّنْيَا وَٱللَّهُ يُرِيدُ ٱلْءَاخِرَةَ وَٱللَّهُ عَزِيزٌ حَكِيمٌ

   It is not fit for a prophet that he should take captives unless he has fought and triumphed in the land; you desire the frail goods of this world, while Allah desires (for you) the hereafter; and Allah is Mighty, Wise.
   

2. 47:4 فَإِذَا لَقِيتُمُ ٱلَّذِينَ كَفَرُوا۟ فَضَرْبَ ٱلرِّقَابِ حَتَّىٰٓ إِذَآ أَثْخَنتُمُوهُمْ فَشُدُّوا۟ ٱلْوَثَاقَ فَإِمَّا مَنًّۢا بَعْدُ وَإِمَّا فِدَآءً حَتَّىٰ تَضَعَ ٱلْحَرْبُ أَوْزَارَهَا ذَٰلِكَ وَلَوْ يَشَآءُ ٱللَّهُ لَٱنتَصَرَ مِنْهُمْ وَلَٰكِن لِّيَبْلُوَا۟ بَعْضَكُم بِبَعْضٍ وَٱلَّذِينَ قُتِلُوا۟ فِى سَبِيلِ ٱللَّهِ فَلَن يُضِلَّ أَعْمَٰلَهُمْ

   So when you meet in battle those who disbelieve, then smite the necks until when you have overcome them, then make (them) prisoners, and afterwards either set them free as a favor or let them ransom (themselves) until the war terminates. That (shall be so); and if Allah had pleased He would certainly have exacted what is due from them, but that He may try some of you by means of others; and (as for) those who are slain in the way of Allah, He will by no means allow their deeds to perish.