Volume 6 · Book 60 · Hadith 234
Narrated Abdullah: During the Pre-lslamic period of ignorance if any tribe became great in number, we used to say, "Amira the children of so-and-so."
— Sahih Bukhari, Volume 6, Book 60: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)), Hadith #234