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

(11) Then if you slide back after the clear signs (Prophet Muhammad صلى الله عليه وسلم and this Qur'an, and Islam) have come to you, then know that Allah is All-Mighty, All-Wise.

(12) Ask the Children of Israel how many clear Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) We gave them. And whoever changes Allah's Favour after it had come to him, [e.g. renounces the Religion of Allah (Islam) and accepts Kufr (disbelief)] then surely, Allah is Severe in punishment.

(13) And do not marry Al-Mushrikat (idolatresses, etc.) till they believe (worship Allah Alone). And indeed a slave woman who believes is better than a (free) Mushrikah (idolatress), even though she pleases you. And give not (your daughters) in marriage to Al-Mushrikun till they believe (in Allah Alone) and verily, a believing slave is better than a (free) Mushrik (idolater), even though he pleases you. Those (Al-Mushrikun) invite you to the Fire, but Allah invites (you) to Paradise and Forgiveness by His Leave, and makes His Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) clear to mankind that they may remember.

(14) And their Prophet (Samuel عليه السلام) said to them: Verily! The sign of His kingdom is that there shall come to you At-Tabut (a wooden box), wherein is Sakinah (peace and reassurance) from your Lord and a remnant of that which Musa (Moses) and Harun (Aaron) left behind, carried by the angels. Verily, in this is a sign for you if you are indeed believers.

(15) Or like the one who passed by a town while it had tumbled over its roofs. He said: "Oh! How will Allah ever bring it to life after its death?" So Allah caused him to die for a hundred years, then raised him up (again). He said: "How long did you remain (dead)?" He (the man) said: "(Perhaps) I remained (dead) a day or part of a day". He said: "Nay, you have remained (dead) for a hundred years, look at your food and your drink, they show no change; and look at your donkey! And thus We have made of you a sign for the people. Look at the bones, how We bring them together and clothe them with flesh". When this was clearly shown to him, he said, "I know (now) that Allah is Able to do all things."

(16) Aforetime, as a guidance to mankind. And He sent down the criterion [of judgement between right and wrong (this Qur'an)]. Truly, those who disbelieve in the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of Allah, for them there is a severe torment; and Allah is All-Mighty, All-Able of Retribution.

(17) Like the behaviour of the people of Fir'aun (Pharaoh) and those before them; they belied Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.). So Allah seized (destroyed) them for their sins. And Allah is Severe in punishment.

(18) There has already been a sign for you (O Jews) in the two armies that met (in combat i.e. the battle of Badr). One was fighting in the Cause of Allah, and as for the other, (they) were disbelievers. They (the believers) saw them (the disbelievers) with their own eyes twice their number (although they were thrice their number). And Allah supports with His Victory whom He wills. Verily, in this is a lesson for those who understand. (See Verse 8:44). (Tafsir At-Tabari)

(19) Truly, the religion with Allah is Islam. Those who were given the Scripture (Jews and Christians) did not differ except, out of mutual jealousy, after knowledge had come to them. And whoever disbelieves in the Ayat (proofs, evidence, verses, signs, revelations, etc.) of Allah, then surely, Allah is Swift in calling to account.

(20) Verily! Those who disbelieve in the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of Allah and kill the Prophets without right, and kill those men who order just dealings, ... then announce to them a painful torment.