Green’s Dictionary of Slang

air v.

[give somewhere the air under air n.]

1. [late 19C] (Aus.) to boast, to talk emptily.

2. [1910s–40s] (US) to dismiss, to jilt.

3. (US) to vilify, to criticize.

4. [1940s–70s] to leave; also as imper.

5. [2010s] (UK black) in social media use, to ignore messages.

SE in slang uses

In phrases

air off oneself (v.) [SE to put on airs]

[20C+] (W.I.) to show off one’s own superior status at others’ expense.

air one’s heels (v.)

[mid-19C–1900s] to loiter about, to dawdle.

air one’s lungs (v.) [SE air, to expose to the air + air, to give expression to]

1. [1910s–40s] (US) to complain, to swear, to curse.

2. [1960s] to argue or talk at length.

air one’s pants (v.)

to idle, to wander.

air one’s paunch (v.) (US, mainly Western)

1. [1920s] to boast, to brag.

2. [1930s–40s] (also air one’s belly) to vomit.

air one’s pores (v.)

[1900s–30s] to be naked.

air one’s tonsils (v.)

[1960s] (US) to talk emptily.

air out (v.) [1940s] (US, orig. black)

1. to go for a walk.

2. (US black) to shoot.

air out one’s mouth on (v.) [SE air, to expose to the air + air, to give expression to]

[20C+] (W.I.) to speak aggressively or abusively.