For someone to be a random retard. A person we don't know, but the only thing we know about them, is that they're a retard. Hence the term, "Rantard."
> GTA Online <
Rantard: *dies*
Heist Host: Fucking rantard. The guy jumped out of the Kuruma almost at the end here and smacked a tree then died. Nice!
Other Heist Associate: Fucking random retard.