End of a fable (5)
I believe the answer is:
moral
'end of a fable' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for moral that I've seen before include "ethical standard" , "Underlying significance of a story or event" , "Concerned with principles of right and wrong" , "Righteous" , "Virtuous and principled" .)