The word(s) "sign" appears 351 time(s) in 320 verse(s) in Quran in Mohsin Khan translation.

(41) And of them there are some who listen to you; but We have set veils on their hearts, so they understand it not, and deafness in their ears; and even if they see every one of the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) they will not believe therein; to the point that when they come to you to argue with you, the disbelievers say: "These are nothing but tales of the men of old."

(42) They indeed are losers who denied their Meeting with Allah, until all of a sudden, the Hour (signs of death) is on them, and they say: "Alas for us that we gave no thought to it," while they will bear their burdens on their backs; and evil indeed are the burdens that they will bear!

(43) If their aversion (from you, O Muhammad صلى الله عليه وسلم and from that with which you have been sent) is hard on you, (and you cannot be patient of their harm to you), then if you were able to seek a tunnel in the earth or a ladder to the sky, so that you may bring them a sign (and you cannot do it, so be patient). And had Allah willed, He could have gathered them together (all) on true guidance, so be not you one of those who are Al-Jahilun (the ignorant).

(44) And they said: "Why is not a sign sent down to him from his Lord?" Say: "Allah is certainly Able to send down a sign, but most of them know not."

(45) Those who reject Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) are deaf and dumb in the darkness. Allah sends astray whom He wills and He guides on the Straight Path whom He wills.

(46) Say (to the disbelievers): "Tell me, if Allah took away your hearing and your sight, and sealed up your hearts, who is there - an ilah (a god) other than Allah who could restore them to you?" See how variously We explain the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.), yet they turn aside.

(47) But those who reject Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.), the torment will touch them for their disbelief (and for their belying the Message of Muhammad صلى الله عليه وسلم). [Tafsir Al-Qurtubi].

(48) When those who believe in Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) come to you, say: "Salamun 'Alaikum" (peace be on you); your Lord has written (prescribed) Mercy for Himself, so that if any of you does evil in ignorance, and thereafter repents and does righteous good deeds (by obeying Allah), then surely, He is Oft-Forgiving, Most Merciful.

(49) And thus do We explain the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) in detail, that the way of the Mujrimun (criminals, polytheists, sinners) may become manifest.

(50) Say: "He has power to send torment on you from above or from under your feet, or to cover you with confusion in party strife, and make you to taste the violence of one another." See how variously We explain the Ayat (proofs, evidence, lessons, signs, revelations, etc.), so that they may understand.