Goat perhaps will go after a neighbour (7)
I believe the answer is:
abutter
'neighbour' is the definition.
(I've seen this before)
'goat perhaps will go after a' is the wordplay.
'goat' becomes 'butt' (synonyms).
'perhaps will' becomes 'er' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'go after' means one lot of letters go next to another.
'butt'+'er'='butter'
'butter' after 'a' is 'ABUTTER'.
Can you help me to learn more?
(Other definitions for abutter that I've seen before include "Neighbour" , "Neighbouring property owner" , "neighbourly sort?" .)