King left hawk with a couple in US state (6)
I believe the answer is:
hawaii
'us state' is the definition.
(I've seen this before)
'king left hawk with a couple' is the wordplay.
'king' becomes 'K' (abbreviation for king in chess).
'left' is a deletion indicator.
'with' is a charade indicator (letters next to each other).
'couple' becomes 'ii' (I've seen this in other clues).
'hawk' with 'k' removed is 'haw'.
'haw'+'a'+'ii'='HAWAII'
'in' is the link.
(Other definitions for hawaii that I've seen before include "It became a US territory in 1900" , "American state" , "50th US state" , "islands" , "Pacific state of USA" .)