(س) اَلِفَ يَاْلَفُ اَلْفًاal-ifa yālafu al-fan: to be familiar with, to be on intimate terms.
(ض) اَلَفَ يَاْلِفُ اَلْفًاal-afa yālifu al-fan: to gather together.
اَلْفٌal-f pl. اٰلَافٌal-āf: thousand, as in three thousand, five thousand. ﴿اَلْفَ سَنَةٍ اِلَّا خَمْسِيْنَ عَامًا﴾ (Al-ʿAnkabūt 29:14); ﴿بِثَلٰثَةِ اٰلٰفٍ مِّنَ الْمَلٰٓئِكَةِ﴾ (Āl ʿImrān 3:124)
اُلُوْفٌulūf: thousands. ﴿وَهُمْ اُلُوْفٌ حَذَرَ الْمَوْتِ﴾ (Al-Baqarah 2:243)
Form II (tafʿīl) اَلَّفَ يُؤَلِّفُ تَاْلِيْفًاal-lafa yuʾallifu tālīfan: to create affection, to bring together. ﴿فَاَلَّفَ بَيْنَ قُلُوْبِكُمْ﴾ (Āl ʿImrān 3:103); ﴿وَالْمُؤَلَّفَةِ قُلُوْبُهُمْ﴾ (At-Tawbah 9:60)
Form IV (ifʿāl) اٰلَفَ يُؤْلِفُ اِيْلَافًاal-afa yuʾlifu īlāfan: to make familiar, to accustom. ﴿لِاِيْلٰفِ قُرَيْشٍ﴾ (Quraysh 106:1)