Surah Al-Mutaffifin 83:5
لِيَوْمٍ عَظِيمٍ
For a tremendous Day -
Translation: Saheeh International
Tafsir
for an awful day that is to say on it and this is the Day of Resurrection
Excerpt from Tafsir al-Jalalayn, commentary on 83:5, via Quran.com. The reader has the full commentary and 9 more tafsirs.