The word(s) "gloom" appears 2 time(s) in 2 verse(s) in Quran in Muhammad Pickthal translation.

(1) But they denied him, so there came on them the retribution of the day of gloom. Lo! it was the retribution of an awful day.

(سورة الشعراء, Ash-Shu'araa, Chapter #26, Verse #189)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)

(2) He created you from one being, then from that (being) He made its mate; and He hath provided for you of cattle eight kinds. He created you in the wombs of your mothers, creation after creation, in a threefold gloom. Such is Allah, your Lord. His is the Sovereignty. There is no Allah save Him. How then are ye turned away?

(سورة الزمر, Az-Zumar, Chapter #39, Verse #6)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)