Chungus comes from the Big Chungus meme that spread online in late 2018, built around an image of a very large Bugs Bunny and used as slang for anything comically oversized. Adding burger turns that idea into a fake, oversized menu item that sounds funny even without context. The phrase circulated in memes, comments and short video edits where users label huge food or make mock orders. It remains popular because it is instantly understood, easy to quote, and works as a shorthand for turning normal meals into exaggerated internet jokes.