Green’s Dictionary of Slang

bust up v.

[SE bust, to break up]

1. [late 19C+] (also bust) to have a major quarrel, to end a love-affair, to divorce.

2. [20C+] to stop something, e.g. a fight, happening.

3. [1920s+] to conclude, e.g. an evening out or a party.

4. [1980s+] (US) to make someone else laugh.

5. see bust v.1