Pejorative nickname for the town of Rodeo, Contra Costa County, California. Probably best known for being hometown to Billie Joe Armstrong of Green Day. Obviously derived from the fact that it is a very boring suburb, where there isn't much to do other than fuck, smoke weed, and do meth.
"She's hella tight dude...."
"Yeah, but she's from Boredeo."
"Weak!"