Bowling spell finished (4)
I believe the answer is:
over
I believe this clue is a double definition.
'bowling spell' is the first definition.
(cricket term)
'finished' is the second definition.
('over' can be similar in meaning to 'finished')
(Other definitions for over that I've seen before include "Having gone < to America" , "remaining" , "See 18" , "Finished - across - in excess" , "Directly above" .)