ف س رf-s-r
(ض) فَسَرَ يَفْسِرُ فَسْرًاfasara yafsiru fasran: to uncover something that is covered; to state the meaning, to make clear. (This verb is not used in the Quran.)
Form II (tafʿīl) فَسَّرَ يُفَسِّرُ تَفْسِيْرًاfassara yufassiru tafsīran: to make the meaning clear gradually and in detail. This root occurs only once in the Quran: ﴿وَلَا يَاْتُوْنَكَ بِمَثَلٍ اِلَّا جِئْنٰكَ بِالْحَقِّ وَاَحْسَنَ تَفْسِيْرًا﴾ (Al-Furqān 25:33)
Form X (istifʿāl) اِسْتَفْسَرَ يَسْتَفْسِرُ اِسْتِفْسَارًاistafsara yastafsiru istifsāran: to seek clarification of a matter; to inquire (this verb is not used in the Quran).