The most common and most likely answer to this crossword clue is the 9 letter word CLEVELAND
I've seen this crossword clue in The Times
C
L
E
V
E
L
A
N
D
More clues leading to the result CLEVELAND
- C+ secures position as President
- Cold, flat area added to north-eastern hilly region
- US President not entirely intelligent to come down to earth
- Cold, even with president
- Heading for Chicago on plane, as well as US port
- Jail director with flat in US city
- Former county college grade with ‘plus’ added
- Steady in honesty, missing our place in Ohio
- President‘s plain sweets that have reduced wrapping
- US President intelligent but not right for leading country
Buddy explains!
The straight part
We know that "north-eastern hilly region" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case north-eastern hilly region = cleveland.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.