The most common and most likely answer to this crossword clue is the 9 letter word SIMPLETON
I've seen this crossword clue in The Guardian
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P
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More clues leading to the result SIMPLETON
- Is backward-looking politician exposed as a fool?
- Fool heading for scandal, one politician revealed
- Charlie‘s terror left during attack
- Is backtracking by politician to reveal a fool?
- … limps badly approaching school dunce
- Fool with money invested in drink disclosed …
- Thick sort of drink’s taken back from William Tell
- Initially shrewd young rascal spilled the beans? Wally!
- Foolish person
- Dope easy to name
Buddy explains!

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.
What does SIMPLETON mean?
SIMPLETON noun- A simple-minded person lacking common sense.