In a manner of speaking, worker lives in a castle traditionally (10)
I believe the answer is:
englishman
'lives in a castle traditionally' is the definition.
I can't tell whether this definition defines the answer.
'in a manner of speaking worker' is the wordplay.
'in a manner of speaking' becomes 'english' (I can't justify this - if you can you should give a lot more credence to this answer).
'worker' becomes 'man' (man is a kind of worker).
'english'+'man'='ENGLISHMAN'
Can you help me to learn more?
(Other definitions for englishman that I've seen before include "who lives in castle?" , "Native" , "Bennett's abroad (Burgess)" , "For example, Ralph Rackstraw" , "E.g. Coward's idiot at 12" .)