A dweebus is the combination of the words "dweeb" and "dingus." It's meant to be used to tease your dweebus friends.
This is meant to be used for someone you really love and don't mind making fun of. Spread the dweebus all around, y'all.
Person 1: "Omg you're such a dweebus."
Person 2: "What does that mean?"
Person 1: "You're just like a class A dweebus. A dingus and a dweeb all in one."
Dweebis is a word used to describe someone who has a lot of body hair, doesn't shower, chain smokes, drinks way too much Mountain Dew, plays video games all day, and likes to swear at everyone.