Athing Mu, center, looking at the final time after the 800 meters.Credit...Hiroko Masuike/The New York Times TOKYO — Before Athing Mu introduced herself to the world at the Tokyo Games, the public-address announcer at Olympic Stadium butchered her name. It was Friday, before her opening round heat of the women’s 800 meters, and Mu did not hide her dismay. “I’m sure everyone saw my face,” said Mu, a 19-year-old American whose name is pronounced “Ah-THING Moe.” “I don’t even know what he said, but it was terrible. Like, where do you even get that from?” Mu said all this with a charming, disarming smile — she was used to people getting her name wrong, she said, but it also seemed clear that she wanted some respect. So she went out and made sure to earn it as an Olympic gold medalist.