Someone who gives a man of kunya because of something he is doing or with one of their names

Sahl ibn Sa'd related that the name which 'Ali, may Allah be pleased with him, liked best was Abu Turab and that he was happy when he was called that. Only the Prophet ﷺ called him that. One day 'Ali was cross with Fatima and went out and reclined against the wall of the mosque. The Prophet ﷺ came to look for him and was told that he was leaning against the wall. The Prophet ﷺ went up to him and found that his back was covered with dust. The Prophet ﷺ began to wipe the dust off his back and said, 'Sit down Abu Turab (father of dust)!'"

حَدَّثَنَا خَالِدُ بْنُ مَخْلَدٍ، قَالَ: حَدَّثَنَا سُلَيْمَانُ بْنُ بِلاَلٍ قَالَ: حَدَّثَنِي أَبُو حَازِمٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، إِنْ كَانَتْ أَحَبَّ أَسْمَاءِ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ إِلَيْهِ لَأَبُو تُرَابٍ، وَإِنْ كَانَ لَيَفْرَحُ أَنْ يُدْعَى بِهَا، وَمَا سَمَّاهُ أَبَا تُرَابٍ إِلاَّ النَّبِيُّ ﷺ، غَاضَبَ يَوْمًا فَاطِمَةَ، فَخَرَجَ فَاضْطَجَعَ إِلَى الْجِدَارِ إِلَى الْمَسْجِدِ، وَجَاءَهُ النَّبِيُّ ﷺ يَتْبَعُهُ، فَقَالَ: هُوَ ذَا مُضْطَجِعٌ فِي الْجِدَارِ، فَجَاءَ النَّبِيَّ ﷺ وَقَدِ امْتَلَأَ ظَهْرُهُ تُرَابًا، فَجَعَلَ النَّبِيُّ ﷺ يَمْسَحُ التُّرَابَ عَنْ ظَهْرِهِ وَيَقُولُ: اجْلِسْ أَبَا تُرَابٍ.