Shrewd king protected by outstanding old nobleman abroad (8)
I believe the answer is:
archduke
'old nobleman abroad' is the definition.
I can't judge whether this defines the answer.
'shrewd king protected by outstanding' is the wordplay.
'shrewd' becomes 'arch' (I've seen this before).
'king' becomes 'K' (chess abbreviation).
'protected by' indicates putting letters inside (inserted letters are held or protected).
'outstanding' becomes 'due' (an outstanding debt is due).
'k' placed within 'due' is 'duke'.
'arch'+'duke'='ARCHDUKE'
Can you help me to learn more?
(Other definitions for archduke that I've seen before include "European nobleman" , "Top nobleman" , "Prince of the former ruling house of Austria, Ferdinand for one" , "Austrian noble" , "noted trio" .)