Surah Al-Mutaffifin 83:31

وَإِذَا ٱنقَلَبُوٓا۟ إِلَىٰٓ أَهْلِهِمُ ٱنقَلَبُوا۟ فَكِهِينَ

And when they returned to their people, they would return jesting.

Translation: Saheeh International

Tafsir

and when they returned to their folks they would return blithely fākihīna a variant reading has fakihīna rejoicing in their disparaging mention of the believers;

Excerpt from Tafsir al-Jalalayn, commentary on 83:31, via Quran.com. The reader has the full commentary and 9 more tafsirs.