Aim to go no further (3)
I believe the answer is:
end
I believe this is a double definition.
'aim' is the first definition.
(both can mean a goal or purpose)
'go no further' is the second definition.
(I've seen this in another clue)
'to' is the link.
(Other definitions for end that I've seen before include "Termination" , "American footballer" , "Closure" , "death" , "Intention" .)