(ض) عَرَفَ يَعْرِفُ عِرْفَانًا وَمَعْرِفَةًʿarafa yaʿrifu ʿirfānan wa-maʿrifatan: to recognise, to know. ﴿يَعْرِفُوْنَهُۥ كَمَا يَعْرِفُوْنَ اَبْنَآءَهُمْ﴾ (Al-Baqarah 2:146)
مَعْرُوْفٌmaʿrūf (passive participle, ism mafʿūl): well known, recognised; good (the opposite of مُنْكَرmunkar).
عُرْفٌʿurf (noun, ism dhāt): custom, usage; goodness. ﴿وَاْمُرْ بِالْمَعْرُوْفِ وَانْهَ عَنِ الْمُنْكَرِ﴾ (Luqmān 31:17)
اَعْرَافٌaʿrāf: elevated places; the name of the wall between Paradise and Hell. ﴿وَعَلَي الْاَعْرَافِ رِجَالٌ﴾ (Al-Aʿrāf 7:46)
Form VI (tafāʿul) تَعَارَفَ يَتَعَارَفُ تَعَارُفًاtaʿārafa yataʿārafu taʿārufan: to recognise one another. ﴿وَجَعَلْنٰكُمْ شُعُوْبًا وَّقَبَآئِلَ لِتَعَارَفُوْا﴾ (Al-Ḥujurāt 49:13)
Form VIII (iftiʿāl) اِعْتَرَفَ يَعْتَرِفُ اِعْتِرَافًاiʿtarafa yaʿtarifu iʿtirāfan: to acknowledge, to confess. ﴿فَاعْتَرَفُوْا بِذَنْۢبِهِمْ﴾ (Al-Mulk 67:11)