No time in prison for this guy (3)
I believe the answer is:
sir
'no time in prison for this guy' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe there's an association between them I don't understand?
This is the entire clue.
Can you help me to learn more?
(Other definitions for sir that I've seen before include "Male form of address" , "Title for knight or teacher" , "Title given to baronet" , "Honorary male title" , "Polite term of address for a man" .)