The word(s) "hidden" appears 34 time(s) in 33 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) From Allah, verily nothing is hidden on earth or in the heavens.

(2) He it is Who has sent down to thee the Book: In it are verses basic or fundamental (of established meaning); they are the foundation of the Book: others are allegorical. But those in whose hearts is perversity follow the part thereof that is allegorical, seeking discord, and searching for its hidden meanings, but no one knows its hidden meanings except Allah. And those who are firmly grounded in knowledge say: "We believe in the Book; the whole of it is from our Lord:" and none will grasp the Message except men of understanding.

(3) One day will Allah gather the messengers together, and ask: "What was the response ye received (from men to your teaching)?" They will say: "We have no knowledge: it is Thou Who knowest in full all that is hidden."

(4) And behold! Allah will say: "O Jesus the son of Mary! Didst thou say unto men, worship me and my mother as gods in derogation of Allah'?" He will say: "Glory to Thee! never could I say what I had no right (to say). Had I said such a thing, thou wouldst indeed have known it. Thou knowest what is in my heart, Thou I know not what is in Thine. For Thou knowest in full all that is hidden.

(5) Say: "I tell you not that with me are the treasures of Allah, nor do I know what is hidden, nor do I tell you I am an angel. I but follow what is revealed to me." Say: "can the blind be held equal to the seeing?" Will ye then consider not?

(6) Then began Satan to whisper suggestions to them, bringing openly before their minds all their shame that was hidden from them (before): he said: "Your Lord only forbade you this tree, lest ye should become angels or such beings as live for ever."

(7) They will present their excuses to you when ye return to them. Say thou: "Present no excuses: we shall not believe you: Allah hath already informed us of the true state of matters concerning you: It is your actions that Allah and His Messenger will observe: in the end will ye be brought back to Him Who knoweth what is hidden and what is open: then will He show you the truth of all that ye did."

(8) And say: "Work (righteousness): Soon will Allah observe your work, and His Messenger, and the Believers: Soon will ye be brought back to the knower of what is hidden and what is open: then will He show you the truth of all that ye did."

(9) In whatever business thou mayest be, and whatever portion thou mayest be reciting from the Qur'an,- and whatever deed ye (mankind) may be doing,- We are witnesses thereof when ye are deeply engrossed therein. Nor is hidden from thy Lord (so much as) the weight of an atom on the earth or in heaven. And not the least and not the greatest of these things but are recorded in a clear record.

(10) "I tell you not that with me are the treasures of Allah, nor do I know what is hidden, nor claim I to be an angel. Nor yet do I say, of those whom your eyes do despise that Allah will not grant them (all) that is good: Allah knoweth best what is in their souls: I should, if I did, indeed be a wrong-doer."