The word(s) "secret" appears 47 time(s) in 46 verse(s) in Quran in Muhammad Habib Shakir translation.

(21) So they disputed with one another about their affair and kept the discourse secret.

(22) They shall consult together secretly: You did tarry but ten (centuries).

(23) Their hearts trifling; and those who are unjust counsel together in secret: He is nothing but a mortal like yourselves; what! will you then yield to enchantment while you see?

(24) (For) those who fear their Lord in secret and they are fearful of the hour.

(25) Say: He has revealed it Who knows the secret in the heavens and the earth; surely He is ever Forgiving, Merciful.

(26) If you do a thing openly or do it in secret, then surely Allah is Cognizant of all things.

(27) And a burdened soul cannot bear the burden of another and if one weighed down by burden should cry for (another to carry) its burden, not aught of it shall be carried, even though he be near of kin. You warn only those who fear their Lord in secret and keep up prayer; and whoever purifies himself, he purifies himself only for (the good of) his own soul; and to Allah is the eventual coming.

(28) Surely they who recite the Book of Allah and keep up prayer and spend out of what We have given them secretly and openly, hope for a gain which will not perish.

(29) You can only warn him who follows the reminder and fears the Beneficent Allah in secret; so announce to him forgiveness and an honorable reward.

(30) Therefore let not their speech grieve you; surely We know what they do in secret and what they do openly.