Surah Al-Qamar 54:6

فَتَوَلَّ عَنْهُمْ ۘ يَوْمَ يَدْعُ ٱلدَّاعِ إِلَىٰ شَىْءٍ نُّكُرٍ

So leave them, [O Muḥammad]. The Day the Caller calls to something forbidding,

Translation: Saheeh International

Tafsir

So turn away from them! this is the import of the preceding statement and it completes what is being said. On the day when the Summoner namely Isrāfīl yawma ‘the day’ is rendered accusative by yakhrujūna ‘they will emerge’ next verse summons to an awful thing read nukur or nukr in the sense of munkar ‘disagreeable’ a …

Excerpt from Tafsir al-Jalalayn, commentary on 54:6, via Quran.com. The reader has the full commentary and 9 more tafsirs.