The Prophet ﷺ said, "You should not say, 'Feed your lord (Rabbaka), help your lord in performing ablution, or give water to your lord, but should say, 'my master (e.g. Feed your master instead of lord etc.) (Saiyidi), or my guardian (Maulai), and one should not say, my slave (Abdi), or my girl-slave (Amati), but should say, my lad (Fatai), my lass (Fatati), and 'my boy (Ghulami).  

أَنَّهُ سَمِعَ أَبَا هُرَيْرَةَ ؓ يُحَدِّثُ عَنِ النَّبِيِّ ﷺ أَنَّهُ قَالَ لاَ يَقُلْ أَحَدُكُمْ أَطْعِمْ رَبَّكَ وَضِّئْ رَبَّكَ اسْقِ رَبَّكَ وَلْيَقُلْ سَيِّدِي مَوْلاَىَ وَلاَ يَقُلْ أَحَدُكُمْ عَبْدِي أَمَتِي وَلْيَقُلْ فَتَاىَ وَفَتَاتِي وَغُلاَمِي