The Prophet ﷺ said, "Do not let the bedouins overcome you regarding the name of your prayer, al-Maghrib." He added, "The bedouins call it al-Isha."
أن النبي ﷺ قال: لا تغلبنكم الأعراب على اسم صلاتكم المغرب، قال: وتقول الأعراب: هي العشاء.
Bukhari narrated it in Mawaqit (563) from Abu Muamar (who is Abdullah bin Amr), he said, Abdul-Warith narrated to us, from Husayn, he said, Abdullah bin Burayda narrated to us, he said, Abdullah Muzani narrated to us, then he related the hadith. Husayn here is Muallim. Abdullah Muzani here is Abdullah bin Mughafal.The name "night prayer" was disliked for this prayer lest confusion arise with the other prayer, but if it is qualified by saying "the earlier night prayer," there is no dislike, as is established in the Sahih, "the later night prayer," from what Anas said, "The Prophet delayed the early part of the later night prayer." Bukhari, Fath al-Bari (44/2).