The Buckeye State (4)
I believe the answer is:
ohio
'the buckeye state' is the definition.
('Ohio' can be a synonym of 'buckeye state')
This is the entire clue.
(Other definitions for ohio that I've seen before include "State of east central US" , "great river" , "The Buckeye State" , "Supporting framework" , "E. central US state" .)