The word(s) "fitnah" appears 13 time(s) in 13 verse(s) in Quran in Mohsin Khan translation.

(11) We hasten unto them with good things. Nay, [it is a fitnah (trial) in this worldly life so that they will have no share of good things in the Hereafter] but they perceive not. [Tafsir Al-Qurtubi].

(12) Make not the calling of the Messenger (Muhammad صلى الله عليه وسلم) among you as your calling one of another. Allah knows those of you who slip away under shelter (of some excuse without taking the permission to leave, from the Messenger (صلى الله عليه وسلم). And let those who oppose the Messenger's (Muhammad صلى الله عليه وسلم) commandment (i.e. his Sunnah - legal ways, orders, acts of worship, statements) (among the sects) beware, lest some fitnah (disbelief, trials, afflictions, earthquakes, killing, overpowered by a tyrant) should befall them or a painful torment be inflicted on them.

(13) And if the enemy had entered from all sides (of the city), and they had been exhorted to Al-fitnah (i.e. to renegade from Islam to polytheism), they would surely have committed it and would have hesitated thereupon but little.