You knew what "resting bitch face" was the first time you heard the term, even without having it explained to you. Think Kristen Stewart, Kanye West, and that lady at your job who always looks like she just sucked a lemon and stepped in poop at the same time.

Point it out and they'll usually say something like "this is just my face, I can't help it," which is true according to one study that found RBF is probably genetic.

Now there's a new study that shows RBF is definitely a real thing, and not just something humans made up to make fun of people. The researchers say they've also pinpointed what it is about the face that makes it bitchy while resting.

We'll start with the first part, how do we know resting bitch face is real? To figure this out, researchers with international research firm Noldus took a bunch of expressionless faces and plugged them into their facial recognition software that can analyze faces for happiness, sadness, anger, fear, surprise, disgust, contempt, and “neutral.”

Only about 3 percent of truly neutral faces registered “little blips of emotion” — a touch of sadness here, a hint of surprise there, wrote The Washington Post.

But when the researchers took "neutral" faces of celebrities well known for having RBF, such as Kanye and K-Stew, and put those into the software, something weird happened. The number of faces registering non-neutral emotions doubled to 6 percent. Something was objectively different, and even a computer could see it. RBF is real, and has nothing to do with the way we emotionally feel about people.

So what makes those faces RBFs? From the Post:

“The big change in percentage came from ‘contempt,’” (one of the researchers) said.

And how exactly does a piece of software measure contempt in a face?

It’s in subtle signals, like “one side of the lip pulled back slightly, the eyes squinting a little,” he explained.

So now its up to science to work on the most important thing: a cure for this resting bitch face epidemic.