The word(s) "day" appears 704 time(s) in 579 verse(s) in Quran in Mohsin Khan translation.

(421) And remember (Hud) the brother of 'Ad, when he warned his people in Al-Ahqaf (the curved sand-hills in the southern part of Arabian Peninsula). And surely, there have passed away warners before him and after him (saying): "Worship none but Allah; truly, I fear for you the torment of a mighty day (i.e. the day of Resurrection)."

(422) And on the day when those who disbelieve will be exposed to the Fire (it will be said to them): "Is this not the truth?" They will say: "Yes, By our Lord!" He will say: "Then taste the torment, because you used to disbelieve!"

(423) Therefore be patient (O Muhammad صلى الله عليه وسلم) as did the Messengers of strong will and be in no haste about them (disbelievers). On the day when they will see that (torment) with which they are promised (i.e. threatened, it will be) as if they had not stayed more than an hour in a single day. (O mankind! this Qur'an is sufficient as) a clear Message (or proclamation to save yourself from destruction). But shall any be destroyed except the people who are Al-Fasiqun (the rebellious against Allah's Command, the disobedient to Allah)?

(424) Muhammad (صلى الله عليه وسلم) is the Messenger of Allah. And those who are with him are severe against disbelievers, and merciful among themselves. You see them bowing and falling down prostrate (in prayer), seeking Bounty from Allah and (His) Good Pleasure. The mark of them (i.e. of their Faith) is on their faces (foreheads) from the traces of prostration (during prayers). This is their description in the Taurat (Torah). But their description in the Injeel (Gospel) is like a (sown) seed which sends forth its shoot, then makes it strong, and becomes thick and it stands straight on its stem, delighting the sowers, that He may enrage the disbelievers with them. Allah has promised those among them who believe (i.e. all those who follow Islamic Monotheism, the religion of Prophet Muhammad صلى الله عليه وسلم till the day of Resurrection) and do righteous good deeds, forgiveness and a mighty reward (i.e. Paradise).

(425) And the Trumpet will be blown - that will be the day whereof warning (had been given) (i.e. the day of Resurrection).

(426) (It will be said to the sinners): "Indeed you were heedless of this. Now We have removed from you your covering, and sharp is your sight this day!"

(427) On the day when We will say to Hell: "Are you filled?" It will say: "Are there any more (to come)?"

(428) "Enter you therein in peace and security - this is a day of eternal life!"

(429) And indeed We created the heavens and the earth and all between them in six days and nothing of fatigue touched Us.

(430) And listen on the day when the caller will call from a near place.