The name which is most disliked by Allah. Sahih al-Bukhari 6206
Arabic hadith text
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، رِوَايَةً قَالَ "أَخْنَعُ اسْمٍ عِنْدَ اللَّهِ ـ وَقَالَ سُفْيَانُ غَيْرَ مَرَّةٍ أَخْنَعُ الأَسْمَاءِ عِنْدَ اللَّهِ ـ رَجُلٌ تَسَمَّى بِمَلِكِ الأَمْلاَكِ". قَالَ سُفْيَانُ يَقُولُ غَيْرُهُ تَفْسِيرُهُ شَاهَانْ شَاهْ.
Translation
Narrated Abu Huraira
The Prophet (ﷺ) said, "The most awful (meanest) name in Allah's sight." Sufyan said more than once, "The most awful (meanest) name in Allah's sight is (that of) a man calling himself king of kings." Sufyan said, "Somebody else (i.e. other than Abu Az-Zinad, a sub-narrator) says: What is meant by 'The king of kings' is 'Shahan Shah.,"