Green’s Dictionary of Slang

bail v.

[SE bail out, to escape from an airplane cockpit]

1. (US black, also bail back) to enjoy oneself.

[US]Z.N. Hurston ‘Story in Harlem Sl.’ in Novels and Stories (1995) 1008: Bailing: having fun.
[US]Pittsburgh Courier (PA) 11 Apr. 20/1: Young Minto Cato is in town after a lengthy stay in Canada bailin’ back.

2. (US campus, also bail off, bale) to leave; thus bail on v.

[US]Current Sl. V:1 1: Bail off, v. To alight from a moving car or engine.
[US]T.R. Houser Central Sl. 25: gettin ready to bale Getting ready to leave a location.
[US]J. Doyle College Sl. Dict. [Internet] bail [UCSB] leave somewhere or skip a class.
[UK]J. Mowry Way Past Cool 11: Them big dudes with their full-auto Uzis, an go bailin warp-seven cause Gordy go the balls to shoot back with this!
[US]C. Hiaasen Lucky You 194: Maybe Chub had bailed.
[US]J. Stahl Plainclothes Naked (2002) 273: You try to bail — huh-uh — a crackhead like Tony’s gonna get paranoid.
[UK]B. Hare Urban Grimshaw 107: Target vehicle crashed, driver and passenger bailed [...].
[US]C. Hiaasen Star Island (2011) 48: What would they do if you said fuck it and then bailed?
[UK]T. Black ‘Killing Time in Las Vegas’ in Killing Time in Las Vegas [ebook] I was getting ready to bail when he finally turned to me.
[Aus]N. Cummins Tales of the Honey Badger [ebook] He was more red than a tradie’s porn collection and bailed down the stairs .

3. to play truant; also in non-school/college context.

[US]J. Doyle College Sl. Dict. [Internet] bail [UCSB] leave somewhere or skip a class.
[US]J. Stahl Plainclothes Naked (2002) 160: He felt slightly guilty about bailing on Chatlak’s funeral.

4. to terminate a relationship, to break up; to abandon in a non-sexual sense.

[US]P. Munro Sl. U. 26: I bailed my girlfriend last night because she was being totally lame.

5. to run.

[US]L. Bing Do or Die (1992) 8: You wonder how many kids have bailed from this bench, and how far they got up that road before they got caught.
[US]K. Scott Monster (1994) 19: Y’all bail, we just busted on some Families!

6. (US black) to strut, to walk in an aggressive manner.

[US]L. Stavsky et al. A2Z 5: bailing – walking in an aggressive fashion; wearing your colors while strolling through rival turf: The brotha be bailing through the hood.

7. to throw away.

[UK]J. Mowry Way Past Cool 215: Ajay! Brett! Tunk! Bail them blades! Nice an far. now!

8. to back down, to abandon a promised act.

[Aus]S. Maloney Big Ask 247: I appreciate your efforts [...] I really do, but I’ve bailed. My best bet was to get out while the going was good.
OnLine Dict. of Playground Sl. [Internet] bail v. to ‘give up’ on something ‘I was supposed to dive off the five metre board but I bailed when I saw how high it really was!’.

In phrases

bail in (v.)

1. to join in, e.g. a fight.

[UK](con. 1980s) I. Welsh Skagboys 80: Matty backed doon but Begbie didnae and ended up battering them both. he wisnae too chuffed wi Matty for no bailin in.

2. (Irish, also bail into) to pick up.

[Ire]P. Howard Miseducation of Ross O’Carroll-Kelly (2004) 95: Heard you tried to bail into some Whore on the Shore last night and crashed and burned. [Ibid.] 119: A total lasher [...] and I wouldn’t mind bailing in there myself.
[Ire]P. Howard Curious Incident of the Dog in the Nightdress 28: You’re trying to bail in.