Green’s Dictionary of Slang

air v.

[give somewhere the air under air n.]

1. (Aus.) to boast, to talk emptily.

[Aus]Dead Bird (Sydney) 29 Mar. 5/2: Our lawyers and statesmen they cut a great dash. / Spouting, and airing, and grabbing the cash.

2. (US) to dismiss, to jilt.

[US]‘Paul Cain’ Fast One (1936) 47: Rose figures on airing everybody he ain’t sure of - he’s got a list .
[US]W. Winchell On Broadway 16 Mar. [synd. col.] A major spot is trying to air its manager.
[US]J.H. O’Hara Pal Joey 6: That personality boy at a downtown hotel has aired the femme that got him the job.
[US]Goldin et al. DAUL 17/2: Air, v. To get rid of. ‘Air that stiff (fool, casual criminal, outsider).’.

3. (US) to vilify, to criticize.

[US]‘Paul Cain’ ‘Black’ in Omnibus (2006) 216: You’re airing Ben - how do we know you’ll play ball with us?

4. to leave; also as imper.

[US]C.S. Montanye ‘Publicity for the Corpse’ in Thrilling Detective Dec. [Internet] ‘Air!’ I said to Lorch and Candell [...] ‘Make it rapid!’.
[UK]C. Gaines Stay Hungry 219: Come on y’all, less air this place.

5. (UK black) in social media use, to ignore messages.

hubpages.com ‘Roadman Slang 10 Jan. [Internet] Airing someone - to be ignoring someone's messages or snapchats online.

SE in slang uses

In phrases

air one’s heels (v.)

to loiter about, to dawdle.

[US] letter in T. Hughes Gone To Texas (1884) 7: They say they let them come on after airing their heels on the platform for twelve hours.
[UK]J. Manchon Le Slang.
[UK]Partridge DSUE (1984) 9/1: mid-C.19–early 20.
air one’s lungs (v.) [SE air, to expose to the air + air, to give expression to]

1. (US) to complain, to swear, to curse.

[US]in DARE.
[US]R.F. Adams Western Words (1968) 4: Airin’ the lungs What the cowboy calls ‘cussin’,’ which seems to be a natural part of his language.

2. to argue or talk at length.

[US]in DARE questionaire.
air one’s pants (v.)

to idle, to wander.

[US]C.G. Booth ‘C.G. Booth’ in Penzler Pulp Fiction (2006) 113: And me out airing my pants.
air one’s paunch (v.) (US, mainly Western)

1. to boast, to brag.

[US]in DARE.

2. (also air one’s belly) to vomit.

[US]R.F. Adams Western Words (1968) 4: Airin’ the paunch What the cowboy calls vomiting.
[US]Eble Campus Sl. Spring 1: air one’s belly – vomit, esp. because of alcohol.
air one’s pores (v.)

to be naked.

[UK] in C. Barr French for Love in DSUE (1984).
air one’s tonsils (v.)

(US) to talk emptily.

[US]G. Cuomo Among Thieves 215: When Orninski opened his mouth, it was because he had something to say. He wasn’t just airing his tonsils.
air out (v.) (US, orig. black)

1. to go for a walk.

[US]Z.N. Hurston ‘Story in Harlem Sl.’ in Novels and Stories (1995) 1001: So this day he was airing out on the Avenue.

2. (US black) to shoot.

Young Zee ‘Jack Mode’ [lyrics] I’mma air his ass out, little punk-ass bitch.