Origin: Somewhere around the 6th time Selena Gomez got back together with Justin Bieber.
Definition: When a person becomes completely hypnotized and infatuated with a total douchebag.
Used in a sentence: I met Katie's new creepy boyfriend and it appears she's come down with a terrible case of Bieberitis.
Have you ever had a friends who's head over heels obsessed with a guy and you just don't see it at all? Like, he's not very good looking, he's not very friendly, he's not all that nice to her-- but somehow, she turns into a pod person around him. Maybe the sex is just that good BUT how could it be that good when you get a serious white man underbite vibe from said fellow? Well, it's very possible that your friend has been struck by a rare and tragic disease known as Bieberitis. It's just as dangerous as Ebola, but luckily not as contagious.
Unfortunately, there really is no cure for Bieberitis. You just have to let your friend ride it out. It may get so bad, you can't even handle talking to her anymore. You may lose all respect for her and avoid hanging out with her all together. Don't be surprised if she has to check herself into rehab to fight the illness. And proceed with caution when she seems to have recovered. Symptoms can lie dormant for awhile. At one point, you may think she's back to her normal self and then... one week later, you see a picture of the two of them on her instagram feed and you're like "NOOOOOOOOO. She's relapsed!"
I wish there was more we could do when our friends are in the throes of a Bieberitis infection. But if Orlando Bloom can't cure it, then there's no hope for the rest of us.
For now, let's just keep Selena Gomez in our thoughts and prayers.