ق ت لq-t-l
(ن) قَتَلَ يَقْتُلُ قَتْلًاqatala yaqtulu qatlan: to put someone to death, to kill. ﴿وَلَا تَقْتُلُوا النَّفْسَ الَّتِيْ حَرَّمَ اللّٰهُ اِلَّا بِالْحَقِّ﴾ (Al-Anʿām 6:151); قَتِيْلٌqatīl (on the pattern of فَعِيْلٌfaʿīl, in the sense of a passive participle, ism mafʿūl): one who is killed, slain.
Form III (mufāʿalah) قَاتَلَ يُقَاتِلُ قِتَالًا وَمُقَاتَلَةًqātala yuqātilu qitālan wa-muqātalatan: to fight one another, to wage war. ﴿وَقَاتِلُوْا فِيْ سَبِيْلِ اللّٰهِ﴾ (Al-Baqarah 2:190)
Form VIII (iftiʿāl) اِقْتَتَلَ يَقْتَتِلُ اِقْتِتَالًاiqtatala yaqtatilu iqtitālan: to fight one another in earnest. ﴿وَلَوْ شَآءَ اللّٰهُ مَا اقْتَتَلُوْا﴾ (Al-Baqarah 2:253)