The most common and most likely answer to this crossword clue is the 10 letter word RUSTICATED
I've seen this crossword clue in Independent
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More clues leading to the result RUSTICATED
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The straight part
We know that "sent down from university" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sent down from university = rusticated.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 RUSTICATED mean?
RUSTICATED verb- To suspend or expel from a college or university.
- To construct in a manner so as to produce jagged or heavily textured surfaces.
- To compel to live in or to send to the countryside; to cause to become rustic.
- To go to reside in the country.