1. [1940s] (US black, also bail back) to enjoy oneself.
2. [1970s+] (US campus, also bail off, bale) to leave; thus bail on v.
3. [1980s+] to play truant; also in non-school/college context.
4. [1980s+] to terminate a relationship, to break up; to abandon in a non-sexual sense.
5. [1990s+] to run.
6. [1990s+] (US black) to strut, to walk in an aggressive manner.
7. [1990s+] to throw away.
8. [2000s] to back down, to abandon a promised act.
1. [1980s+] to join in, e.g. a fight.
2. [2000s] (Irish, also bail into) to pick up.