Dogwhistle

A dogwhistle is a word, term or argument secretly used by a group to identify other members of the group, or signal to them in some way. It is called a dogwhistle because dogs can hear high-pitched sound frequencies that humans cannot, hence the dogwhistle is an argument that people outside of the group will not pick up on.

The alt-right, or more aptly named the crypto-fascist contingent, makes heavy use of dogwhistles online not only to signal their beliefs to other fascists, but also to make rehearsed arguments about their beliefs, dressing them up in a veneer of respectability so that liberals will not call them out on it, and instead respect their "freedom of speech." While the word is mostly associated with this circle nowadays, it can be used in a variety of settings but would usually be considered pejorative if used for anyone other than fascists.

Dogwhistles change and evolve with time as they become known outside the group. Since fascists don't actually believe in anything, they can change their dogwhistles at the drop of a hat. See for example the "okay" hand sign: the gesture has existed in Anglo countries since the 1800s at the very least to mean "okay". In 2017, the website 4chan started propagating the hoax that this then-innocuous sign (at least in Anglo countries; the gesture can be an insult in some parts of the world) was a fascist symbol to mean "white power". After the media reported on the story, crypto-fascists started using the hand sign in their pictures as a dogwhistle while dismissing people calling them out for it as falling victim to a "hoax".

In 2019, an Australian white supremacist who killed more than 50 people carrying out an indiscriminate shooting spree in mosques in Christchurch, New Zealand, flashed the okay hand sign as he entered court for his trial.