The most common and most likely answer to this crossword clue is the 9 letter word ROISTERER
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R
More clues leading to the result ROISTERER
- OTT party type could make Tories err
- Tories excited about Republican who might join the party?
- Terrorise madly a noisy reveller.
- Terrorise appallingly noisy party animal
- Possibly terrorise a noisy carouser
- King on steroids? Not half — Queen’s a pleasure-seeker!
- Terrier so bubbly — he's a party animal
- Reveller in middle of throng, one with conduct about right
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.