Exit toll (5,5)
I believe the answer is:
death knell
'exit toll' is the definition.
'death knell' can be an answer for 'exit' (thesaurus). I'm not sure about the 'toll' bit.
'exit toll' is the wordplay.
'exit' becomes 'death'.
'toll' becomes 'knell' (I've seen this before).
'death'+'knell'='DEATH-KNELL'
Can you help me to learn more?
(Other definitions for death knell that I've seen before include "passing on rings" , "Bell rung when someone's popped their clogs" , "Passing on ring" , "Parting note" , "This will end all the hopes" .)