Originated as a nickname. A person referred to as a butt-dink is a total and all out turd of a person. They are generally goofy and awkward, especially in public places. They often try to impress girls with stupid humor but rarely succeed, therefore resorting to homosexuality later in life. They will never succeed at anything and eventually give up.
"That kid was like 28 when he graduated form highschool as a virgin, what a Butt-dink!"