Gunner I'd shot is suffering (8)
I believe the answer is:
enduring
'suffering' is the definition.
('endure' can be a synonym of 'suffer')
'gunner i'd shot' is the wordplay.
'shot' indicates an anagram.
'gunner'+'id'='gunnerid'
'gunnerid' is an anagram of 'ENDURING'.
'is' acts as a link.
(Other definitions for enduring that I've seen before include "Lasting, unceasing" , "stable ..." , "having lasting qualities" , "Long-lasting" , "Going through" .)