Enlightening (8)
I believe the answer is:
edifying
'enlightening' is the definition.
(I know that enlightening can be written as edifying)
This is all the clue.
(Other definitions for edifying that I've seen before include "Improving the mind" , "Intellectually or morally stimulating" , "Instructional" , "Morally improving" , "Instructive - uplifting" .)