Chapter on the Reasons Behind Hajj
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 3|Chapter 1
وَ سُمِّيَتْ بَكَّةَ لِأَنَّ اَلنَّاسَ يَبُكُّ بَعْضُهُمْ بَعْضاً فِيهَا بِالْأَيْدِي.
It is named Bakkah because people crowd against one another there, pressing with their hands.
- Ṣaḥīḥ al-Faqīh