He was bound to serve his master (7)
I believe the answer is:
villein
This clue could be a double definition.
'he' is the first definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'bound to serve his master' is the second definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'was' is the link.
Can you help me to learn more?
(Other definitions for villein that I've seen before include "Feudal tenant" , "Subject" , "Feudal peasant" , "vassal" , "Lowly worker" .)