The word(s) "lest" appears 73 time(s) in 69 verse(s) in Quran in Abdullah Yusuf Ali translation.

(21) The Hypocrites are afraid lest a Sura should be sent down about them, showing them what is (really passing) in their hearts. Say: "Mock ye! But verily Allah will bring to light all that ye fear (should be revealed).

(22) But none believed in Moses except some children of his people, because of the fear of Pharaoh and his chiefs, lest they should persecute them; and certainly Pharaoh was mighty on the earth and one who transgressed all bounds.

(23) Perchance thou mayest (feel the inclination) to give up a part of what is revealed unto thee, and thy heart feeleth straitened lest they say, "Why is not a treasure sent down unto him, or why does not an angel come down with him?" But thou art there only to warn! It is Allah that arrangeth all affairs!

(24) He said: "O Noah! He is not of thy family: For his conduct is unrighteous. So ask not of Me that of which thou hast no knowledge! I give thee counsel, lest thou act like the ignorant!"

(25) Noah said: "O my Lord! I do seek refuge with Thee, lest I ask Thee for that of which I have no knowledge. And unless thou forgive me and have Mercy on me, I should indeed be lost!"

(26) "And O my people! let not my dissent (from you) cause you to sin, lest ye suffer a fate similar to that of the people of Noah or of Hud or of Salih, nor are the people of Lut far off from you!

(27) Said (the father): "My (dear) little son! relate not thy vision to thy brothers, lest they concoct a plot against thee: for Satan is to man an avowed enemy!

(28) (Jacob) said: "Really it saddens me that ye should take him away: I fear lest the wolf should devour him while ye attend not to him."

(29) She said: "There before you is the man about whom ye did blame me! I did seek to seduce him from his (true) self but he did firmly save himself guiltless!.... and now, if he doth not my bidding, he shall certainly be cast into prison, and (what is more) be of the company of the vilest!"

(30) And He has set up on the earth mountains standing firm, lest it should shake with you; and rivers and roads; that ye may guide yourselves;