Hadith 8:3195
Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Sufyan narrated to us, from Ibn Abi Najih, from Mujahid, who said: The Ka’bah was only named [as such] because it is square. And the *budn* (sacrificial camels) were only named [as such] because of their fatness.
حدثنا أبو بكر قال نا وكيع قال نا سفيان عن بن أبي نجيح عن مجاهد قال إنما سميت الكعبة لأنها مربعة وإنما سميت البدن من أجل السمانة