Is polite and has half of the durian, not being one to engage in combat (8)
I believe the answer is:
civilian
'durian not being one to engage in combat' is the definition.
I can't tell whether this defines the answer.
'is polite and has half of' is the wordplay.
'is polite' becomes 'civil' (synonyms).
'and' becomes 'n' (common abbreviation for 'and').
'has' means one lot of letters go next to another.
'half of' becomes 'ia' (I am not sure about this - if you are sure you should believe this answer much more).
'n' after 'ia' is 'ian'.
'civil'+'ian'='CIVILIAN'
'the' acts as a link.
Can you help me to learn more?
(Other definitions for civilian that I've seen before include "Nonmilitary person" , "Citizen (non-military)" , "Non-combatant" , "Forces apart any person" , "He's not in the clergy or military" .)