Healthy British socialist, genteel (8)
I believe the answer is:
wellbred
'genteel' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives occasionally define each other.
'healthy british socialist' is the wordplay.
'healthy' becomes 'well' (associated in meaning).
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'socialist' becomes 'red' (red can informally mean a socialist).
'well'+'b'+'red'='WELLBRED'
Can you help me to learn more?
(Another definition for wellbred that I've seen is " Educated in good manners".)