Definition
Synonym of bad news (“irritating, troublesome or harmful thing, situation or person”).
Origins
From bad + business.
Also Said As
How People Actually Use It
1. Any sort of morally ambiguous activity. 2. Anything displeasant. 3. Criminal acts.
"1. I think Bill got into some bad business with Wendy and her man last night. 2. That mole on her back is bad business. 3. Whatever those guys are up to in the parking lot, it's got to be bad business."
Source: Urban Dictionary