The most common and most likely answer to this crossword clue is the 9 letter word BIFURCATE
I've seen this crossword clue in Financial Times
B
I
F
U
R
C
A
T
E
Buddy explains!
The straight part
We know that "to split two ways" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case to split two ways = bifurcate.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 BIFURCATE mean?
BIFURCATE verb- To divide or fork into two channels or branches.
- To cause to bifurcate.
- Divided or forked into two; bifurcated.
- Having bifurcations.