Good spirits falling short of ecstasy (5)
I believe the answer is:
moral
'good' is the definition.
('moral' is associated in meaning with 'good')
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for moral that I've seen before include "Honourable" , "Practical lesson to be drawn from an experience" , "Virtuous and principled" , "Lesson that can be drawn from a story" , "Concerned with principles of right and wrong" .)