Incalculable (6)
I believe the answer is:
untold
'incalculable' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for untold that I've seen before include "Lots" , "Too many to be counted; not narrated" , "missing relations" , "Not narrated or measured" , "Story yet to be read" .)