Metaphysical (14)
I believe the answer is:
transcendental
'metaphysical' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for transcendental that I've seen before include "Pi is" , "Supereminent" , "'being in the spiritual realms' maybe" , "like a number of mathematicians?" , "Relating to the spiritual realm" .)