لَمَّا رَآنِي قَدْ نَزَلْتُ أُرِيدُهُ أَبْدَى نَوَاجِذَهُ لِغَيْرِ تَبَسُّمِ
When he saw me dismount and come for him, he bared his back teeth—but not in a smile.
Nawājidh means the rear teeth. The qualifier li-ghayri tabassum excludes a smile: the exposed teeth express dread, rage or grim effort. One facial detail carries the psychological tension of the encounter.