Sort of army reputed to lose my exit (9)
I believe the answer is:
departure
'exit' is the definition.
(I know that exit can be written as departure)
'sort of army reputed to lose my' is the wordplay.
'sort of' is an anagram indicator.
'to lose' indicates named letters should be taken away.
'army'+'reputed'='armyreputed'
'armyreputed' with 'my' removed is 'arreputed'.
'arreputed' anagrammed gives 'DEPARTURE'.
(Other definitions for departure that I've seen before include "The act of going away" , "new approach" , "Not the usual" , "change of direction" , "Exit" .)