Conned king for power, medal and lordly title (7)
I believe the answer is:
dukedom
'title' is the definition.
(I have seen 'Hereditary title ' mean 'dukedom' so perhaps 'title' could also mean 'dukedom')
'conned king for power medal and lordly' is the wordplay.
I cannot really see how this works, but
'king' could be 'k' (chess abbreviation) and 'k' is present in the answer.
'medal' could be 'om' (Order of Merit) and 'om' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for dukedom that I've seen before include "Noble rank" , "Noble's position" , "Top peerage rank" , "Highest title of aristocracy" , "Title or lands of high ranking nobleman" .)