The acronym stands for Olympic Athlete(s) from Russia
Russian athletes must compete under this title instead of the Russian flag due to the Russian doping scandal, the end result of which is that the world is basically pretending like Russia isn't competing even though, you know, they actually are under the banner of OAR.
The scandal first emerged in the McLaren Report, which alleged more than 1,000 Russian athletes partook in or benefitted from a state-sponsored cover-up for athletes using performance-enhance drugs (PEDs).
The second part of the report was published after the Rio Games in 2016. A subsequent International Olympic Committee (IOC) investigation resulted in the Russian Olympic Committee being barred from the 2018 Winter Olympics. The nation's flag won't appear during the opening ceremony, and government officials are not allowed to attend the Games.
If they're banned, why are Russians competing?
Despite the ban, which came down in December, the IOC decided to allow Russian athletes with no history of doping to compete. Though, they aren't allowed to compete under the Russian flag. Those athletes will compete as an Olympic Athlete from Russia.
Around 400 athletes were told they could compete if they could prove they hadn't broken any doping rules. Ultimately, Russia named 169 athletes to the non-Russian Russian team.
As if that wasn't complicated enough, the Court of Arbitration for Sport is considering appeals from 47 Russian athletes who say they should be allowed to compete this year. That list includes a pair of gold medal winners from the last Winter Games. The final decision may come as late as Thursday night or Friday morning, according to a report by The New York Times. (The latter is the day of the opening ceremony, and the former is the first day of Olympic competition.)
Many athletes think the situation is ridiculous. The IOC had many years to figure this out. Moreover, some athletes have said they believe it's a sign that the IOC doesn't care enough about whether or not athletes take PEDs.
"I think that the timing of all this is ridiculous," Lowell Bailey, an American biathlete, told the Times. He said the IOC should acknowledge it bears some responsibility for the confusion. "I think it did fail clean athletes," he said. There are almost 10 biathletes from Russia who are part of the appeal process.
Dick Pound of the World Anti-Doping Agency (WADA) felt similarly. "The IOC has not only failed to protect clean athletes but has made it possible for cheating athletes to prevail against the clean athletes," he said at a meeting in South Korea on Tuesday per the Express.