cut up vs split up

To disintegrate; to break into pieces. 

To lacerate; to wound by multiple lacerations; to injure or damage by cutting, or as if by cutting. 

To move aggressively in front of another vehicle while driving. 

To behave like a clown or jokester (a cut-up); to misbehave; to act in a playful, comical, boisterous, or unruly manner to elicit laughter, attention, etc. 

Comprise a particular selection of runners. 

To cut into smaller pieces, parts, or sections. 

To distress mentally or emotionally. 

separate, disassociate, cause to come apart. 

Cease to be together, break apart from the group.