Skibidi is a slang term that is currently used to mean cool, bad, or dumb, depending on context. It appeared sometime in 2023 or 2024, and is probably going to stick around for a while, although I predict some solidification of semantic content at some point.
Skibidi is a nonsense word taken from the title of the popular animated (machinima) web series-cum-war-movie-atmospheric-electronic-music-video Skibidi Toilet, which is about toilets with human heads fighting people with surveillance cameras, TVs, drills, and other mechanical bits for heads. It is cool, bad, and dumb.