ھ و رh-w-r
(ن) هَارَ يَهُوْرُ هَوْرًاhāra yahūru hawran (original form: هَوَرَ يَهْوُرُhawara yahwuru): (of a building or a bank) to fall, to collapse. (This verb is not used in the Quran.)
هَارٍhār (active participle, ism fāʿil; regularly هَائِرٌhāʾir, and with metathesis هَارٍhār is also in use): about to fall, hollow. Only once in the Quran (in the verse of the next line).
Form VII (infiʿāl) اِنْهَارَ يَنْهَارُ اِنْهِيَارًاinhāra yanhāru inhiyāran: to fall down, to collapse. Only once in the Quran: ﴿عَلٰى شَفَا جُرُفٍ هَارٍ فَانْهَارَ بِهِۦ فِيْ نَارِ جَهَنَّمَ﴾ (At-Tawbah 9:109)