The most common and most likely answer to this crossword clue is the 9 letter word HUMDINGER
I've seen this crossword clue in The Daily Telegraph
H
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More clues leading to the result HUMDINGER
- Fabulous example of bell doubling as buzzer?
- Lulu longing to entertain married princess
- Head of Mafia caught by hired gun, surprisingly — wow!
- Excellent example of medic, one that stops craving
- Hot, brewed in red mug, wonderful thing
- A beauty has boss and I overwhelmed by lust
- Dim recollection in desire for something else
- Fine example of smell associated with campanologist?
- Disturbed mind in bigger one that’s really big
- Drone accompanying bell perhaps, amazing thing
Buddy explains!

The straight part
We know that "amazing thing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case amazing thing = humdinger.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 HUMDINGER mean?
HUMDINGER noun- Something that is particularly outstanding, unusual, or exceptional.