The word(s) "prone" appears 3 time(s) in 3 verse(s) in Quran in Mohsin Khan translation.

(1) Those who will be gathered to Hell (prone) on their faces, such will be in an evil state, and most astray from the (Straight) Path.

(2) And whoever brings an evil deed (i.e. Shirk - polytheism, disbelief in the Oneness of Allah and every evil sinful deed), they will be cast down (prone) on their faces in the Fire. (And it will be said to them) "Are you being recompensed anything except what you used to do?"

(3) Is he who walks prone (without seeing) on his face, more rightly guided, or he who (sees and) walks upright on the Straight Way (i.e. Islamic Monotheism)?