The word(s) "back" appears 225 time(s) in 216 verse(s) in Quran in Abdullah Yusuf Ali translation.

(171) Hearken ye to your Lord, before there come a Day which there will be no putting back, because of (the Ordainment of) Allah! that Day there will be for you no place of refuge nor will there be for you any room for denial (of your sins)!

(172) In order that ye may sit firm and square on their backs, and when so seated, ye may celebrate the (kind) favour of your Lord, and say, "Glory to Him Who has subjected these to our (use), for we could never have accomplished this (by ourselves),

(173) "And to our Lord, surely, must we turn back!"

(174) And he left it as a Word to endure among those who came after him, that they may turn back (to Allah).

(175) And blessed is He to Whom belongs the dominion of the heavens and the earth, and all between them: with Him is the Knowledge of the Hour (of Judgment): and to Him shall ye be brought back.

(176) "Then bring (back) our forefathers, if what ye say is true!"

(177) If any one does a righteous deed, it ensures to the benefit of his own soul; if he does evil, it works against (his own soul). In the end will ye (all) be brought back to your Lord.

(178) And when Our Clear Signs are rehearsed to them their argument is nothing but this: They say, "Bring (back) our forefathers, if what ye say is true!"

(179) Those who turn back as apostates after Guidance was clearly shown to them,- the Evil One has instigated them and busied them up with false hopes.

(180) But how (will it be) when the angels take their souls at death, and smite their faces and their backs?