On getting exhausted, turned in (7)
I believe the answer is:
retired
'turned in' is the definition.
('retire' can be a synonym of 'turn in')
'on getting exhausted' is the wordplay.
'on' becomes 're' (regarding).
'getting' is a charade indicator (letters next to each other).
'exhausted' becomes 'tired' (exhausted can mean very tired).
're'+'tired'='RETIRED'
(Other definitions for retired that I've seen before include "Gave up job, relaxed on pension" , "went back" , "claiming a pension?" , "No longer active in work or profession" , "out of office?" .)