បណ្ណារក្ស (Khmer) comes from Pali paṇṇā, from Sanskrit रक्षा, from Sanskrit रक्ष्, from Proto-Indo-Aryan Hrakṣ-, from Proto-Indo-Iranian Hrakš-, from Proto-Indo-European h₂lek- — to protect.
បណ្ណារក្ស (Khmer): librarian