What the hell do you think it means, dumbass?
It means someone who's so fucking stupid, their brain must be an ass.
(Looking at you, dumbass)
You fucking dumbass! Go die in a hellhole! Ya fucking moron.
You fucking dumbass, literally anyone can make a definition here. To cite urban dictionary as a valid way to define words is just utter stupidity
You think roses are blue? You’re Mariela Gomez dumbass
John: Hey bro, I just bought a new NFT!
Bob: Why would you do that you dumbass