The word(s) "witness" appears 123 time(s) in 99 verse(s) in Quran in Mohsin Khan translation.

(61) And strive hard in Allah's Cause as you ought to strive (with sincerity and with all your efforts that His Name should be superior). He has chosen you (to convey His Message of Islamic Monotheism to mankind by inviting them to His religion of Islam), and has not laid upon you in religion any hardship: it is the religion of your father Ibrahim (Abraham) (Islamic Monotheism). It is He (Allah) Who has named you Muslims both before and in this (the Qur'an), that the Messenger (Muhammad صلى الله عليه وسلم) may be a witness over you and you be witnesses over mankind! So perform As-Salat (Iqamat-as-Salat), give Zakat and hold fast to Allah [i.e. have confidence in Allah, and depend upon Him in all your affairs]. He is your Maula (Patron, Lord), what an Excellent Maula (Patron, Lord) and what an Excellent Helper!

(62) The fornicatress and the fornicator, flog each of them with a hundred stripes. Let not pity withhold you in their case, in a punishment prescribed by Allah, if you believe in Allah and the Last Day. And let a party of the believers witness their punishment. (This punishment is for unmarried persons guilty of the above crime, but if married persons commit it (illegal sex), the punishment is to stone them to death, according to Allah's Law).

(63) And those who accuse chaste women, and produce not four witnesses, flog them with eighty stripes, and reject their testimony forever. They indeed are the Fasiqun (liars, rebellious, disobedient to Allah).

(64) And for those who accuse their wives, but have no witnesses except themselves, let the testimony of one of them be four testimonies (i.e. testifies four times) by Allah that he is one of those who speak the truth.

(65) But it shall avert the punishment (of stoning to death) from her, if she bears witness four times by Allah, that he (her husband) is telling a lie.

(66) Why did they not produce four witnesses? Since they (the slanderers) have not produced witnesses! Then with Allah they are the liars.

(67) On the Day when their tongues, their hands, and their legs (or feet) will bear witness against them as to what they used to do.

(68) And those who do not bear witness to falsehood, and if they pass by some evil play or evil talk, they pass by it with dignity.

(69) They said: "Swear one to another by Allah that we shall make a secret night attack on him and his household, and thereafter we will surely say to his near relatives: 'We witnessed not the destruction of his household, and verily we are telling the truth.'"

(70) And you (O Muhammad صلى الله عليه وسلم) were not on the western side (of the Mount), when We made clear to Musa (Moses) the commandment, and you were not among the witnesses.