The word(s) "grievous" appears 89 time(s) in 89 verse(s) in Quran in Abdullah Yusuf Ali translation.

(51) Those who love (to see) scandal published broadcast among the Believers, will have a grievous Penalty in this life and in the Hereafter: Allah knows, and ye know not.

(52) Those who slander chaste women, indiscreet but believing, are cursed in this life and in the Hereafter: for them is a grievous Penalty,-

(53) Deem not the summons of the Messenger among yourselves like the summons of one of you to another: Allah doth know those of you who slip away under shelter of some excuse: then let those beware who withstand the Messenger's order, lest some trial befall them, or a grievous penalty be inflicted on them.

(54) (Allah will say): "Now have they proved you liars in what ye say: so ye cannot avert (your penalty) nor (get) help." And whoever among you does wrong, him shall We cause to taste of a grievous Penalty.

(55) And the people of Noah,- when they rejected the messengers, We drowned them, and We made them as a Sign for mankind; and We have prepared for (all) wrong-doers a grievous Penalty;-

(56) Those who say, "Our Lord! avert from us the Wrath of Hell, for its Wrath is indeed an affliction grievous,-

(57) They will not believe in it until they see the grievous Penalty;

(58) Such are they for whom a grievous Penalty is (waiting); and in the Hereafter theirs will be the greatest loss.

(59) Those who reject the Signs of Allah and the Meeting with Him (in the Hereafter),- it is they who shall despair of My Mercy: it is they who will (suffer) a most grievous Penalty.

(60) When Our Signs are rehearsed to such a one, he turns away in arrogance, as if he heard them not, as if there were deafness in both his ears: announce to him a grievous Penalty.