Green’s Dictionary of Slang

bust-up n.

1. [mid-19C+] (also burst-up) lit., an explosion; fig., a serious quarrel or argument, a fight; also attrib. [SE bust, to break].

2. [mid-19C+] (also burst-up) a collapse, either emotional or financial [bust v.1 ].

3. [late 19C] a day off [bust n.].

4. [1930s] a rowdy party [bust n.].

5. [2010s] (UK Und.) a share-out, a division of spoils.

6. see bust n. (2b)

7. see bust n. (3a)