Sunan Abi Dawud

Narrated AbuHurayrah: The Prophet (ﷺ) said: None of you must say: ""My slave"" (abdi) and ""My slave-woman"" (amati), and a slave must not say: ""My lord"" (rabbi or rabbati). The master (of a slave) should say: ""My young man"" (fataya) and ""My young woman"" (fatati), and a slave should say ""My master"" (sayyidi) and ""My mistress"" (sayyidati), for you are all (Allah's slave and the Lord is Allah, Most High)