He was captured many years after (7)
I believe the answer is:
hostage
'he was captured' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'many years after' is the wordplay.
'many' becomes 'host' (I've seen this in other clues).
'years' becomes 'age' (period of many years).
'after' says to put letters next to each other.
'host'+'age'='HOSTAGE'
Can you help me to learn more?
(Other definitions for hostage that I've seen before include "Detainee - gash toe (anag)" , "Captive held for ransom" , "One held captive" , "Person held by kidnapper for ransom" , "Prisoner - pawn" .)