It was the collective "ewww"; heard around the Twitterverse.
Miley Cyrus - a.k.a. former Disney innocent Hannah Montana - shocked even the unshockable during MTV's Music Video Awards Sunday, sending tweeters into overdrive when she bent over in her flesh-colored two piece and rubbed her hiney against Robin Thicke's crotch.
Talk about blurred lines.
What? Is she serious? Why does she have that big foam finger? And what in the heck is she doing?
Here is a primer: Twerking can be done alone or with a partner. It involves one dancer (usually a woman) gyrating backward against another person, her behind jiggling. Can we say sexually explicit?
It seemed there was something wrong with the 20-year-old Cyrus twerking with the very married Robin Thicke during the performance of his hit, "Blurred Lines."
What about all those little kids who loved their Hannah Montana? Do they really need to see that?
And then there was the rub of Cyrus performing with a bevy of curvy black women as her backup dancers. In "We Can't Stop," Cyrus pays homage "to my homegirls here with the big butt shaking it like we at a strip club."
Nothing like using someone else's culture to prove your authenticity while making them your props.
"At the core of capitalism from the days of minstrel shows until now has been about selling black bodies," said James Peterson, director of Africana Studies at Lehigh University. "The black woman's body is unfortunately the subject of those forces."
"It's just a clumsy white appropriation of black culture," said Salamishah Tillet, associate professor of English at the University of Pennsylvania. "That is just part of the larger trend we were seeing in music and pop culture that night."
Tillet was referring to Thicke's Blurred Lines hit, which, ironically, has led him to preemptively sue Marvin Gaye's estate to protect himself from accusations of copyright infringement (it seems even he acknowledges the similarity to Gaye's "Got to Give It Up). And Justin Timberlake, anointed the president of pop, showed off moves eerily similar to Michael Jackson's.
Twerking is a fairly recent cultural phenomenon.
Until the 1990s, the dance moves were confined to strip clubs. Toward the end of the decade, southern rap artists like Juvenile and Mystikal began celebrating the joys of dancing with voluptuous women, and the style moved out into the open, in dance clubs.
In 2001, Usher released "Twork It Out." The song wasn't about dancing, but lovemaking.
As artists from the South got more popular, twerking became a staple dance in rap videos
And with social media, it took on a form of forbidden flirting, much like sexting.
"Social media has really changed how we have looked at the word," said Pamela Mitchell, founder of the Washington, D.C.-based Hip Hop Scholars Competition.
"Now there is just one meaning. And it became widely known and understood as a part of black culture through social media."
It seems 2013 is looking like the year of the twerk.
Earlier this year, Cyrus released a video of herself twerking dressed like a bear. In June, Georgia rapper Cash Out released "The Twerk Song," and last month, Busta Rhymes teamed up with Nicki Minaj for a reggae-inspired dance-hall jam, "Twerk It."
Just this weekend, rapper Juicy J. offered to "give out a 50k scholarships to the best chick that can twerk."
He has since rescinded his generous offer.