Naval jail and a potential inmate (7)
I believe the answer is:
brigand
'a potential inmate' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'naval jail and' is the wordplay.
'naval jail' becomes 'brig' (I've seen this in another clue).
'brig'+'and'='BRIGAND'
Can you help me to learn more?
(Other definitions for brigand that I've seen before include "Marauder" , "Criminal" , "Plunderer" , "thief" , "Robber - darn big (anag)" .)