The most common and most likely answer to this crossword clue is the 9 letter word IMPROMPTU
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More clues leading to the result IMPROMPTU
- Off-the-cuff claim to be on time at university
- Island politician with easy win — trade union unprepared
- The writer's cue initially unthinkingly unscripted
- I have arrived dead on time? You, one hears,unprepared
- Ad lib concert after the writer's put out
- Compiler is ready – solver reportedly unprepared
- After one term of maximum power, old Trump explodes spontaneously
- Spontaneous instant message by President Trump’s raving about nothing
- Boast of good timekeeper texting you on the spur of the moment
- I’m on time at university, yet unprepared
Buddy explains!

The straight part
We know that "unprepared" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unprepared = impromptu.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 IMPROMPTU mean?
IMPROMPTU noun- A short musical composition for an informal occasion often with the character of improvisation and usually to be played solo.
- (by extension) Any composition, musical or otherwise, that is created on the spot without preparation.
- Improvised; without prior preparation, planning or rehearsal.