A celebrity. Originally coined for a very famous or successful celebrity but now routinely used to describe anyone who has public exposure.(noun)
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Use "megastar" in a sentence
"Jennifer Hudson was famously a failed American Idol contestant before she became a Dreamgirls megastar, which is an incredible achievement – you can't see the same thing happening to, say, Chico from X Factor – so you could say that Jennifer Hudson Day was well-deserved."
"We know the megastar is a private person, but we'd like to see his handsome face just once in a while!"
"After "megastar" Peppa Pig was stopped from appearing at a Labour Party mini-manifesto launch by her licensing company, Children's Secretary Ed Balls said: "Peppa did tell me that not only is she a supporter of universal Sure Start but would be quite worried if George Pig lost his child trust fund.""