The word(s) "secret" appears 40 time(s) in 40 verse(s) in Quran in Muhammad Pickthal translation.

(1) He said: O Adam! Inform them of their names, and when he had informed them of their names, He said: Did I not tell you that I know the secret of the heavens and the earth? And I know that which ye disclose and which ye hide.

(2) Men are in charge of women, because Allah hath made the one of them to excel the other, and because they spend of their property (for the support of women). So good women are the obedient, guarding in secret that which Allah hath guarded. As for those from whom ye fear rebellion, admonish them and banish them to beds apart, and scourge them. Then if they obey you, seek not a way against them. Lo! Allah is ever High, Exalted, Great.

(3) Those are they, the secrets of whose hearts Allah knoweth. So oppose them and admonish them, and address them in plain terms about their souls.

(4) There is no good in much of their secret conferences save (in) him who enjoineth almsgiving and kindness and peace-making among the people. Whoso doeth that, seeking the good pleasure of Allah, We shall bestow on him a vast reward.

(5) If ye do good openly or keep it secret, or forgive evil, lo! Allah is ever Forgiving, Powerful.

(6) This day are (all) good things made lawful for you. The food of those who have received the Scripture is lawful for you, and your food is lawful for them. And so are the virtuous women of the believers and the virtuous women of those who received the Scripture before you (lawful for you) when ye give them their marriage portions and live with them in honour, not in fornication, nor taking them as secret concubines. Whoso denieth the faith, his work is vain and he will be among the losers in the Hereafter.

(7) And thou seest those in whose heart is a disease race toward them, saying: We fear lest a change of fortune befall us. And it may happen that Allah will vouchsafe (unto thee) the victory, or a commandment from His presence. Then will they repent them of their secret thoughts.

(8) O ye who believe! Allah will surely try you somewhat (in the matter) of the game which ye take with your hands and your spears, that Allah may know him who feareth Him in secret. Whoso transgresseth after this, for him there is a painful doom.

(9) He is Allah in the heavens and in the earth. He knoweth both your secret and your utterance, and He knoweth what ye earn.

(10) Say: Who delivereth you from the darkness of the land and the sea? Ye call upon Him humbly and in secret, (saying): If we are delivered from this (fear) we truly will be of the thankful.