Just like a “catfish” (of which, see), a catfash uses a fake social media account replete with fake profile pic to dupe others, but with the aim of anonymously spreading fascist ideas.

See also: reply guy; incel
I can’t tweet anything these days without my DMs getting inundated with catfash.
by An Sionnach December 7, 2020
Get the catfash mug.