Fixed goal (6)
I believe the answer is:
target
'fixed goal' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for target that I've seen before include "Object to be attained by archers (or fund raisers?)" , "Object to be aimed at" , "Objective, mark" , "A result to aim at" , "Goal to be aimed for" .)