Young Sheldon reveals the origin of 'bazinga,' Sheldon's favorite word

Anyone who watches The Big Bang Theory knows that one of Sheldon's go-to words is bazinga—but there's never been an explanation for how he came up with such a unique saying. That is, until now.

On Thursday's episode of Young Sheldon—the TBBT spin-off that also airs on CBS—the title character, played by Iain Armitage, embarks on a quest to inject more frivolity into his life and goes to a comic book store in search of "practical-joke paraphernalia so I may behave childishly."

The clerk directs him to a red-and-yellow display of toys from Bazinga, a novelty company out of Toledo, Ohio. The company's slogan is, "If it's funny, it's a Bazinga!"

"Interesting," observes Sheldon.

Sheldon then tries out his novelties jokes on his dad and brother, including a mixed-nut can that conceals a pop-out snake and a gum package that snaps at the victim's thumb when they try to grab a piece. Every time Sheldon "nails" his prey, he proudly proclaims, "bazinga!"

By the end of the episode, he tricks his sister into sitting on a whoopee cushion. "That's how I becamse the madcap prankster all my friends know and love," says a grown-up Sheldon (voiced by Jim Parsons).

Better late than never with the explanation: TBBT will end its 12-season run in 2019. Young Sheldon, however, will continue.

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