The word(s) "back" appears 101 time(s) in 98 verse(s) in Quran in Muhammad Pickthal translation.

(21) They indeed are losers who deny their meeting with Allah until, when the Hour cometh on them suddenly, they cry: Alas for us, that we neglected it! They bear upon their backs their burdens. Ah, evil is that which they bear!

(22) Say: Shall we cry, instead of unto Allah, unto that which neither profiteth us nor hurteth us, and shall we turn back after Allah hath guided us, like one bewildered whom the devils have infatuated in the earth, who hath companions who invite him to the guidance (saying): Come unto us? Say: Lo! the guidance of Allah is Guidance, and we are ordered to surrender to the Lord of the Worlds,

(23) And they say: Such cattle and crops are forbidden. No-one is to eat of them save whom we will - in their make-believe - cattle whose backs are forbidden, cattle over which they mention not the name of Allah. (All that is) a lie against Him. He will repay them for that which they invent.

(24) Unto those who are Jews We forbade every animal with claws. And of the oxen and the sheep forbade We unto them the fat thereof save that upon the backs or the entrails, or that which is mixed with the bone. That we awarded them for their rebellion. And lo! we verily are truthful.

(25) O ye who believe! When ye meet those who disbelieve in battle, turn not your backs to them.

(26) Whoso on that day turneth his back to them, unless manoeuvring for battle or intent to join a company, he truly hath incurred wrath from Allah, and his habitation will be hell, a hapless journey's end.

(27) And when He made you (Muslims), when ye met (them), see them with your eyes as few, and lessened you in their eyes, (it was) that Allah might conclude a thing that must be done. Unto Allah all things are brought back.

(28) If thou couldst see how the angels receive those who disbelieve, smiting faces and their backs and (saying): Taste the punishment of burning!

(29) And if thou fearest treachery from any folk, then throw back to them (their treaty) fairly. Lo! Allah loveth not the treacherous.

(30) Allah hath given you victory on many fields and on the day of Huneyn, when ye exulted in your multitude but it availed you naught, and the earth, vast as it is, was straitened for you; then ye turned back in flight;