(3) باب حُكْمِ إِطْلاَقِ لَفْظَةِ الْعَبْدِ وَالأَمَةِ وَالْمَوْلَى وَالسَّيِّدِ
Abu Huraira reported Allah's Messenger (ﷺ) so many ahadith and one of them is this that Allah's Messenger (ﷺ) said:
None of you should say: Supply drink to your lord, feed your lord, help your lord in performing ablution, and none of you should say: My Lord. He should say: My chief, my patron; and none of you should say: My bondman, my slave-girl, but simply say: My boy, my girl, my servant.
Reference: Sahih Muslim 2249 d
In-book reference: Book 40, Hadith 16
USC-MSA web (English) reference(deprecated numbering scheme): Book 27, Hadith 5594