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

(41) Moses said to him: Woe to you! Forge not ye a lie against Allah, lest He destroy you (at once) utterly by chastisement: the forger must suffer frustration!"

(42) (Saying): "Eat of the good things We have provided for your sustenance, but commit no excess therein, lest My Wrath should justly descend on you: and those on whom descends My Wrath do perish indeed!

(43) (Aaron) replied: "O son of my mother! Seize (me) not by my beard nor by (the hair of) my head! Truly I feared lest thou shouldst say, 'Thou has caused a division among the children of Israel, and thou didst not respect my word!'"

(44) And We have set on the earth mountains standing firm, lest it should shake with them, and We have made therein broad highways (between mountains) for them to pass through: that they may receive Guidance.

(45) It is He Who created the Night and the Day, and the sun and the moon: all (the celestial bodies) swim along, each in its rounded course.

(46) O mankind! if ye have a doubt about the Resurrection, (consider) that We created you out of dust, then out of sperm, then out of a leech-like clot, then out of a morsel of flesh, partly formed and partly unformed, in order that We may manifest (our power) to you; and We cause whom We will to rest in the wombs for an appointed term, then do We bring you out as babes, then (foster you) that ye may reach your age of full strength; and some of you are called to die, and some are sent back to the feeblest old age, so that they know nothing after having known (much), and (further), thou seest the earth barren and lifeless, but when We pour down rain on it, it is stirred (to life), it swells, and it puts forth every kind of beautiful growth (in pairs).

(47) But verily thou callest them to the Straight Way;

(48) "And I seek refuge with Thee O my Lord! lest they should come near me."

(49) Deem not the summons of the Messenger among yourselves like the summons of one of you to another: Allah doth know those of you who slip away under shelter of some excuse: then let those beware who withstand the Messenger's order, lest some trial befall them, or a grievous penalty be inflicted on them.

(50) (Pharaoh) said: "Show it then, if thou tellest the truth!"