he fought a man and one of them bit the other, who pulled his forearm away from his mouth, and a front tooth fell out. The matter was referred to the Prophet and he said: "Would one of you bite his brother as a young camel bites?" And judged it to be invalid. (Using translation from Nasāʾī 4763)  

أَنَّهُ قَاتَلَ رَجُلًا فَعَضَّ أَحَدُهُمَا صَاحِبَهُ فَانْتَزَعَ يَدَهُ مِنْ فِيهِ فَقَلَعَ سِنَّهُ فَرُفِعَ ذَلِكَ إِلَى النَّبِيِّ ﷺ فَقَالَ «يَعَضُّ أَحَدُكُمْ أَخَاهُ كَمَا يَعَضُّ الْبَكْرُ» فَأَبطَلَهَا  

a man from Banu Tamim fought with another man, and he bit his hand, so he pulled it away and a front tooth fell out. They referred the dispute to the Messenger of Allah, who said: "Would one of you bite his brother as a young camel bites?" and he thwarted it, meaning he judged it to be invalid. (Using translation from Nasāʾī 4764)  

أَنَّ رَجُلًا مِنْ بَنِي تَمِيمٍ قَاتَلَ رَجُلًا فَعَضَّ يَدَهُ فَانْتَزَعَهَا فَأَلْقَى ثَنِيَّتَهُ فَاخْتَصَمَا إِلَى رَسُولِ اللهِ ﷺ فَقَالَ «يَعَضُّ أَحَدُكُمْ أَخَاهُ كَمَا يَعَضُّ الْبَكْرُ» فَأَطَلَّهَا أَيْ أَبْطَلَهَا