dumbass

A classic, all-purpose insult for a stupid person that can be used many ways, this particular definition writer prefers to use it for people who do idiotic things that they should know better than to do, and which, due to their own stupidity, end up with them getting hurt, getting suckered out of their money or otherwise taken advantage of, or suffering other ill fortune. People who brought it on themselves. Some people think the term originated with Beavis and Butt-head, but that's actually not true, that show just popularized the term. It's at least as old as Star Trek IV (1986), and probably older than that. While the show That '70s Show came out later, and is fictional, the character of Red Forman in that show was also known for using the term and so, if the show is an accurate depiction of the time, then people were using the term in the '70s as well.