Interminable annoyance for god (4)
I believe the answer is:
thor
'for god' is the definition.
(Thor is an example)
'interminable annoyance' is the wordplay.
'interminable' means to remove the last letter (without the letter which terminates the word).
'annoyance' becomes 'thorn' (thorn is a kind of annoyance).
'thorn' with its final letter taken off is 'THOR'.
(Other definitions for thor that I've seen before include "The Thunderer" , "Mythical figure" , "Thunderous god" , "Scandinavian thunder-god" , "Norse god of thunder - a weekday is named after him" .)