A short dialogue from the movie Extraterrestrial (2014):
— It’s been ten years, Alan. Now look. I mean no disrespect, but it is time to face reality, man. She left you.
— People have been trying to convince me that she just split town, just took off with another guy. People have been saying it so long I almost believed it myself, but now I know what happened.
I’ve been searching online and couldn’t find this idiom in any dictionary. Though, from the context I think I can infer that it probably means something like skipped town, which is a real idiom. Am I on the right track with this?
A meaning of split that is at least bordering on slang that means to leave somewhere, often quickly or without caring to tell anyone (see def. 13 here).
This party is boring. Let’s split.
I haven’t seen them around. They must have split.
So split town in this sense means to leave town. Split town itself isn’t an idiom or well-known phrase.