Puncture that’s a real pain in the neck! (4)
I believe the answer is:
bore
'pain in the neck' is the definition.
'puncture that's a real' is the wordplay.
'puncture' becomes 'bor' (I am not sure about this - if you are sure you should believe this answer much more).
'that's a real' becomes 'e' (e is a kind of real).
'bor'+'e'='BORE'
Can you help me to learn more?
(Other definitions for bore that I've seen before include "Held" , "I go on" , "Hollow barrel" , "Irritate" , "Hollow out; dull person" .)