Gun fire explodes round the ship (7)
I believe the answer is:
frigate
'ship' is the definition.
(frigate is a kind of ship)
'gun fire explodes round' is the wordplay.
'gun' becomes 'gat' (US informal term for a gun).
'explodes' is an anagram indicator.
'round' means one lot of letters goes inside another.
'fire' with letters rearranged gives 'frie'.
'gat' placed inside 'frie' is 'FRIGATE'.
'the' is the link.
(Other definitions for frigate that I've seen before include "Warship; -- bird" , "US warship" , "Type of warship" , "Naval escort vessel" , "Light warship" .)