1. ACAB (A.C.A.B).
All Coppers Are Bastards / All Cops Are Bastards.
Origionally used by strikers in the UK, spread to prison inmates who often tattoo'd ACAB on themselves.

In the 70's became popular in the punk/oi scenes after the band 4-Skins used it as the title for a song.

Alternative defenitions are often used to avoid getting in trouble when quized on its mening, for example a march in germany had a banner proclaiming All Communists Are Beautiful.

2. ACAB - Anti Cuts Action Bristol, a local campaigning group fighting against austerity cuts and their root causes; capitalism and hierarchy.

3. Association of Community Access Broadcasters, a group of New Zealand community radio stations.

A word or phrase used by angry white teens when they get caught doing a 70 in a 55

All chunguses are big

Ridiculous trend made mostly by twitter users, but it's pretty popular on Reddit too. ACAB translates to All Cops Are Bastards/Bad.

All Cops Are Bastards

An acronym that stands for A Crazy Ass Bitch, try to avoid people that use this acronym especially if they have it in their Instagram bios underneath their gender pronouns. These people will attack you if you don’t share the same opinion and are overly sensitive. Most people who use ACAB are typically young white women.

The short for "All Communists Are Bad"