The most common and most likely answer to this crossword clue is the 7 letter word SLIP-UP
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L
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P
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U
P
More clues leading to the result SLIP-UP
- Overturned more than one schoolboy error
- Blunder made by son taking sauce at university
- Backing students, a mistake
- Raised student's mistake
- Mistake students raised
- . Mistake that misdirects students
- Backward kids in school, a failure
- Upset students making careless mistake
- Upcoming student’s mistake
- School children overturned – a minor mistake
Buddy explains!

The straight part
We know that "Blunder" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blunder = slip-up.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 SLIP-UP mean?
SLIP-UP noun- A (small) error or mistake; a (minor) misstep.