The word(s) "witness" appears 111 time(s) in 90 verse(s) in Quran in Muhammad Pickthal translation.

(1) And if ye are in doubt concerning that which We reveal unto Our slave (Muhammad), then produce a surah of the like thereof, and call your witness beside Allah if ye are truthful.

(2) And when We made with you a covenant (saying): Shed not the blood of your people nor turn (a party of) your people out of your dwellings. Then ye ratified (Our covenant) and ye were witnesses (thereto).

(3) Thus We have appointed you a middle nation, that ye may be witnesses against mankind, and that the messenger may be a witness against you. And We appointed the qiblah which ye formerly observed only that We might know him who followeth the messenger, from him who turneth on his heels. In truth it was a hard (test) save for those whom Allah guided. But it was not Allah's purpose that your faith should be in vain, for Allah is Full of Pity, Merciful toward mankind.

(4) And of mankind there is he whoso conversation on the life of this world pleaseth thee (Muhammad), and he calleth Allah to witness as to that which is in his heart; yet he is the most rigid of opponents.

(5) O ye who believe! When ye contract a debt for a fixed term, record it in writing. Let a scribe record it in writing between you in (terms of) equity. No scribe should refuse to write as Allah hath taught him, so let him write, and let him who incurreth the debt dictate, and let him observe his duty to Allah his Lord, and diminish naught thereof. But if he who oweth the debt is of low understanding, or weak, or unable himself to dictate, then let the guardian of his interests dictate in (terms of) equity. And call to witness, from among your men, two witnesses. And if two men be not (at hand) then a man and two women, of such as ye approve as witnesses, so that if the one erreth (through forgetfulness) the other will remember. And the witnesses must not refuse when they are summoned. Be not averse to writing down (the contract) whether it be small or great, with (record of) the term thereof. That is more equitable in the sight of Allah and more sure for testimony, and the best way of avoiding doubt between you; save only in the case when it is actual merchandise which ye transfer among yourselves from hand to hand. In that case it is no sin for you if ye write it not. And have witnesses when ye sell one to another, and let no harm be done to scribe or witness. If ye do (harm to them) lo! it is a sin in you. Observe your duty to Allah. Allah is teaching you. And Allah is knower of all things.

(6) Allah (Himself) is witness that there is no Allah save Him. And the angels and the men of learning (too are witness). Maintaining His creation in justice, there is no Allah save Him the Almighty, the Wise.

(7) But when Jesus became conscious of their disbelief, he cried: Who will be my helpers in the cause of Allah? The disciples said: We will be Allah's helpers. We believe in Allah, and bear thou witness that we have surrendered (unto Him).

(8) Our Lord! We believe in that which Thou hast revealed and we follow him whom Thou hast sent. Enrol us among those who witness (to the truth).

(9) Say: O People of the Scripture! Come to an agreement between us and you: that we shall worship none but Allah, and that we shall ascribe no partner unto Him, and that none of us shall take others for lords beside Allah. And if they turn away, then say: Bear witness that we are they who have surrendered (unto Him).

(10) O People of the Scripture! Why disbelieve ye in the revelations of Allah, when ye (yourselves) bear witness (to their truth)?