The most common and most likely answer to this crossword clue is the 6 letter word SCHISM
I've seen this crossword clue in The Guardian
S
C
H
I
S
M
More clues leading to the result SCHISM
- School is beginning to mend split
- Division in mollusc: his membrane
- School is beginning to mask serious divergence of opinions
- Coy at first, the bloke’s into S & M, causing rupture
- A division of the Church
- Hosts taken aback about man’s separation
- School ideology creating division
- Artless Christmas pudding, causes rift
- Second church with distinctive doctrine comes from this?
- Major split in church is dividing ends of spectrum
Buddy explains!

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 SCHISM mean?
SCHISM noun- A split or separation within a group or organization, typically caused by discord.
- A formal division or split within a religious body.
- A split within Christianity whereby a group no longer recognizes the Bishop of Rome as the head of the Church, but shares essentially the same beliefs with the Church of Rome. In other words, a political split without the introduction of heresy.