• تَحْنَثْ
• حِنث

Appears 2 times in the Quran.

1. 38:44 وَخُذْ بِيَدِكَ ضِغْثًا فَٱضْرِب بِّهِۦ وَلَا تَحْنَثْ إِنَّا وَجَدْنَٰهُ صَابِرًا نِّعْمَ ٱلْعَبْدُ إِنَّهُۥٓ أَوَّابٌ

   And take in your hand a green branch and beat her with It and do not break your oath; surely We found him patient; most excellent the servant! Surely he was frequent m returning (to Allah).
   

2. 56:46 وَكَانُوا۟ يُصِرُّونَ عَلَى ٱلْحِنثِ ٱلْعَظِيمِ

   And they persisted in the great violation.