Result of an action (6)
I believe the answer is:
effect
'result of an action' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for effect that I've seen before include "Pocket pistol" , "'Result, consequence (6)'" , "Meaning < to force" , "Result of action, or cause to happen" , "Grounds for an act" .)