From Sahih Muslim (Hadith 1455):
Abdullah b. 'Umar reported:I heard the Messenger of Allah (ﷺ) 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
Reference: Muslim 1455