The word(s) "hidden" appears 22 time(s) in 21 verse(s) in Quran in Mohsin Khan translation.

(11) [As Shaitan (Satan) has barred them from Allah's Way] so they do not worship (prostrate themselves before) Allah, Who brings to light what is hidden in the heavens and the earth, and knows what you conceal and what you reveal. [Tafsir At-Tabari]

(12) And there is nothing hidden in the heaven and the earth but it is in a Clear Book (i.e. Al-Lauh Al-Mahfuz).

(13) See you not (O men) that Allah has subjected for you whatsoever is in the heavens and whatsoever is in the earth, and has completed and perfected His Graces upon you, (both) apparent (i.e. Islamic Monotheism, and the lawful pleasures of this world, including health, good looks, etc.) and hidden [i.e. One's Faith in Allah (of Islamic Monotheism) knowledge, wisdom, guidance for doing righteous deeds, and also the pleasures and delights of the Hereafter in Paradise]? Yet of mankind is he who disputes about Allah without knowledge or guidance or a Book giving light!

(14) No person knows what is kept hidden for them of joy as a reward for what they used to do.

(15) (Delicate and pure) as if they were (hidden) eggs (well) preserved.

(16) He said: "I did love the good (these horses) instead of remembering my Lord (in my 'Asr prayer)" till the time was over, and (the sun) had hidden in the veil (of night).

(17) The Day when they will (all) come out, nothing of them will be hidden from Allah. Whose is the kingdom this Day? (Allah Himself will reply to His Question): It is Allah's the One, the Irresistible!

(18) Verily, those who turn away from Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc. by attacking, distorting and denying them) are not hidden from Us. Is he who is cast into the Fire better or he who comes secure on the Day of Resurrection? Do what you will. Verily He is All-Seer of what you do (this is a severe threat to the disbelievers ).

(19) Or do those in whose hearts is a disease (of hypocrisy), think that Allah will not bring to light all their hidden ill-wills?

(20) That Day shall you be brought to Judgement, not a secret of you will be hidden.