The most common and most likely answer to this crossword clue is the 7 letter word RUPTURE
I've seen this crossword clue in The Times
R
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More clues leading to the result RUPTURE
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The straight part
We know that "Schism" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case schism = rupture.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 RUPTURE mean?
RUPTURE noun- A burst, split, or break.
- A social breach or break, between individuals or groups.
- A break or tear in soft tissue, such as a muscle.
- A failure mode in which a tough ductile material pulls apart rather than cracking.
- To burst, break through, or split, as under pressure.
- To dehisce irregularly.