Fate of king is settled (6)
I believe the answer is:
kismet
'fate' is the definition.
(kismet is a kind of fate)
'king is settled' is the wordplay.
'king' becomes 'k'.
'settled' becomes 'met' (I've seen this in other clues).
'k'+'is'+'met'='KISMET'
'of' acts as a link.
(Other definitions for kismet that I've seen before include "Broadway musical" , "fortune" , "Will of Allah" , "Fate - 1953 musical" , "Destiny; 50s musical" .)