Aim for support but don't hit this (8)
I believe the answer is:
goalpost
'don't hit this' is the definition.
The definition suggests a singular noun which matches the answer.
'aim for support' is the wordplay.
'aim' becomes 'goal' (I've seen this before).
'for' means one lot of letters go next to another.
'support' becomes 'post' (post is a kind of support).
'goal'+'post'='GOALPOST'
'but' acts as a link.
Can you help me to learn more?
(Other definitions for goalpost that I've seen before include "one unfairly moved" , "it's unfair to move" , "One propping up the bar" , "Upright with net attached" , "woodwork" .)