The word(s) "secret" appears 43 time(s) in 42 verse(s) in Quran in Mohsin Khan translation.

(11) Say (O Muhammad صلى الله عليه وسلم): "Come, I will recite what your Lord has prohibited you from: Join not anything in worship with Him; be good and dutiful to your parents; kill not your children because of poverty - We provide sustenance for you and for them; come not near to Al-Fawahish (shameful sins, illegal sexual intercourse) whether committed openly or secretly; and kill not anyone whom Allah has forbidden, except for a just cause (according to Islamic law). This He has commanded you that you may understand.

(12) Say (O Muhammad صلى الله عليه وسلم): "(But) the things that my Lord has indeed forbidden are Al-Fawahish (great evil sins and every kind of unlawful sexual intercourse) whether committed openly or secretly, sins (of all kinds), unrighteous oppression, joining partners (in worship) with Allah for which He has given no authority, and saying things about Allah of which you have no knowledge."

(13) Invoke your Lord with humility and in secret. He likes not the aggressors.

(14) Do you think that you shall be left alone while Allah has not yet tested those among you who have striven hard and fought and have not taken Walijah [(Bitanah - helpers, advisors and consultants from disbelievers, pagans.) giving openly to them their secrets] besides Allah, and His Messenger, and the believers. Allah is Well-Acquainted with what you do.

(15) Know they not that Allah knows their secret ideas, and their Najwa (secret counsels), and that Allah is the All-Knower of things unseen.

(16) No doubt! They did fold up their breasts, that they may hide from Him. Surely, even when they cover themselves with their garments, He knows what they conceal and what they reveal. Verily, He is the All-Knower of the (innermost secrets) of the breasts.

(17) They [(Yusuf's (Joseph) brothers] said: "If he steals, there was a brother of his [Yusuf (Joseph)] who did steal before (him)." But these things did Yusuf (Joseph) keep in himself, revealing not the secrets to them. He said (within himself): "You are in worst case, and Allah is the Best Knower of that which you describe!"

(18) And those who remain patient, seeking their Lord's Countenance, perform As-Salat (Iqamat-as-Salat), and spend out of that which We have bestowed on them, secretly and openly, and defend evil with good, for such there is a good end.

(19) Say (O Muhammad صلى الله عليه و سلم) to 'Ibadi (My slaves) who have believed, that they should perform As-Salat (Iqamat-as-Salat ), and spend in charity out of the sustenance We have given them, secretly and openly, before the coming of a Day on which there will be neither mutual bargaining nor befriending.

(20) Allah puts forward the example of (two men - a believer and a disbeliever); a slave (disbeliever) under the possession of another, he has no power of any sort, and (the other), a man (believer) on whom We have bestowed a good provision from Us, and he spends thereof secretly and openly. Can they be equal? (By no means). All the praises and thanks are to Allah. Nay! (But) most of them know not.