The most common and most likely answer to this crossword clue is the 8 letter word SUNDERED
I've seen this crossword clue in The Times
S
U
N
D
E
R
E
D
More clues leading to the result SUNDERED
Buddy explains!

The straight part
We know that "Split" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case split = sundered.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 SUNDERED mean?
SUNDERED verb- To break or separate or to break apart, especially with force.
- To part, separate.
- To expose to the sun and wind.