A person or a living creature that might be as smart as a tree thump. It is used as an insult when they do something incredibly retarded or dumb.
Why are you such a dumbass?
You are such a fucking dumbass.
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