(from Buddha Heruka)
“Akashic Records”
is a term given by a channeler years ago because he could relate to that term.
“Akasha” refers to a king who lived many aeons ago. This channeler had a special connection to that King, so the channeler understood what he was accessing to be like a library or collection of all that King’s realizations.
That king actually became, when he attained Enlightenment, Buddha Akshobya, who is the head of one of the five Buddha families.
ALL ABOUT ENLIGHTENMENT 
Thanks for this. I have heard the term used often, and have occasionally wondered its origin. Interesting that its etymology is eponymous and Buddhist!
Yes, I was delighted to learn that too!