Akasha is a Sanskrit word which means either 'sky' or spirit'. If you have been socially conditioned in the West you might be more familiar with the Western term God or some other name or word which means a godhead or divine creative force or being. However this is not to say that akasha is God because akasha is always formless and is not connected in any way to physicality or physical form.
What akasha refers to is the fundamental core essential quality of the universe which is either ultimate reality or the void or spirit (because if you remember consciousness and space can be one and the same thing).
You are the universe, the universe is you
This is what lies behind the above statement because the ultimate reality of who are is the same as the ultimate reality of the universe - it is akasha or spirit.