Chapter: The beginning of the time for Maghrib when the sun sets
Abdullah b. 'Umar reported: I heard the Messenger of Allah ( صلی اللہ علیہ وسلم ) as saying: Let the bedouin not gain upper hand over you in regard to the name of your prayer. See I (The night prayer should be called) 'Isya' (and the bedouins call it Atama (because) they milk their camels late.
Authentic