The word(s) "darkness" appears 37 time(s) in 34 verse(s) in Quran in Mohsin Khan translation.

(21) And (remember) Dhun-Nun (Jonah), when he went off in anger, and imagined that We shall not punish him (i.e. the calamities which had befallen him)! But he cried through the darkness (saying): La ilaha illa Anta [none has the right to be worshipped but You (O, Allah)], Glorified (and Exalted) be You [above all that (evil) they associate with You]! Truly, I have been of the wrong-doers."

(22) Or [the state of a disbeliever] is like the darkness in a vast deep sea, overwhelmed with waves topped by waves, topped by dark clouds, (layers of) darkness upon darkness: if a man stretches out his hand, he can hardly see it! And he for whom Allah has not appointed light, for him there is no light.

(23) Is not He (better than your gods) Who guides you in the darkness of the land and the sea, and Who sends the winds as heralds of glad tidings, going before His Mercy (rain)? Is there any ilah (god) with Allah? High Exalted be Allah above all that they associate as partners (to Him)!

(24) He it is Who sends Salat (His blessings) on you, and His angels too (ask Allah to bless and forgive you), that He may bring you out from darkness (of disbelief and polytheism) into light (of Belief and Islamic Monotheism). And He is Ever Most Merciful to the believers.

(25) Nor are (alike) darkness (disbelief) and light (Belief in Islamic Monotheism).

(26) And a sign for them is the night. We withdraw therefrom the day, and behold, they are in darkness.

(27) He created you (all) from a single person (Adam); then made from him his wife [Hawwa' (Eve)]. And He has sent down for you of cattle eight pairs (of the sheep, two, male and female; of the goats, two, male and female; of the oxen, two, male and female; and of the camels, two, male and female). He creates you in the wombs of your mothers: creation after creation in three veils of darkness. Such is Allah your Lord. His is the kingdom. La ilaha illa Huwa (none has the right to be worshipped but He). How then are you turned away?

(28) It is He Who sends down manifest Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) to His slave (Muhammad صلى الله عليه وسلم) that He may bring you out from darkness into light. And verily, Allah is to you full of kindness, Most Merciful.

(29) (And has also sent to you) a Messenger (Muhammad صلى الله عليه وسلم), who recites to you the Verses of Allah (the Qur'an) containing clear explanations, that He may take out those who believe and do righteous good deeds, from the darkness (of polytheism and disbelief) to the light (of Islamic Monotheism). And whosoever believes in Allah and performs righteous good deeds, He will admit him into Gardens under which rivers flow (Paradise) to dwell therein forever. Allah has indeed granted for him an excellent provision.

(30) And We have made the night as a covering (through its darkness),