Region from Ohio to the Rockies (7)
I believe the answer is:
midwest
'region from ohio to the rockies' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for midwest that I've seen before include "American region" , "US region" , "Region from Ohio to the Rockies" , "North central region of the United States" , "somewhere in America" .)