The word(s) "tremendous" appears 8 time(s) in 8 verse(s) in Quran in Saheeh International translation.

(1) Indeed, Allah does not forgive association with Him, but He forgives what is less than that for whom He wills. And he who associates others with Allah has certainly fabricated a tremendous sin.

(2) Say, "Indeed I fear, if I should disobey my Lord, the punishment of a tremendous Day."

(3) We had certainly sent Noah to his people, and he said, "O my people, worship Allah; you have no deity other than Him. Indeed, I fear for you the punishment of a tremendous Day.

(4) And when Our verses are recited to them as clear evidences, those who do not expect the meeting with Us say, "Bring us a Qur'an other than this or change it." Say, [O Muhammad], "It is not for me to change it on my own accord. I only follow what is revealed to me. Indeed I fear, if I should disobey my Lord, the punishment of a tremendous Day."

(5) Then the factions differed [concerning Jesus] from among them, so woe to those who disbelieved - from the scene of a tremendous Day.

(6) When you received it with your tongues and said with your mouths that of which you had no knowledge and thought it was insignificant while it was, in the sight of Allah, tremendous.

(7) Say, "Indeed I fear, if I should disobey my Lord, the punishment of a tremendous Day."

(8) For a tremendous Day -