[20C+] cheek, sarcasm.
[1900s] an unpleasant, ill-tempered person.
[1910s+] to act contrarily, aggressively, to argue; to be unpleasant or offensive, to speak in a caustic or sarcastic manner, sometimes with affection.
[1950s–70s] to inform on, to tell tales about, to poison someone’s mind against.
1. [1900s] (Aus.) to render impoverished; thus acid school, a gambling venue that takes its clients’ cash (prob. via cheating) .
2. [20C+] (Aus.) to exert pressure on a person for a loan, a favour, sexual compliance etc [supposedly orig. used by gold assayers who tested ‘real’ gold with acid].
3. [1910s] to speak sarcastically, aggressively.
4. [1910s] to put a stop to.
5. [1910s] to confirm.
6. [1910s–20s] to test out a person or statement.
[1900s–20s] (US) to stand up under pressure, to maintain one’s composure.
[1910s] (Aus.) to speak honestly, without sarcasm.