Other than Grimes revealing that she’d had a second child with tech entrepreneur Elon Musk via surrogate, the singer detailed what her daughter Exa Dark Sideræl Musk‘s full name means for a Thursday March 10 profile in Vanity Fair. The 33-year-old singer (whose real name is Claire Boucher) revealed that she and the 50-year-old billionaire call their daughter Y, but like their first child X Æ A-Xii (X AE A-XII), their daughter’s name has a very special meaning.
Grimes explained that Y’s first name is a reference to the computing term exaFLOP, which is an acronym for “Floating Points Operations Per Second,” according to PCMag. An exaFLOP is being able to perform one quintillion of those operations in a second. While Y’s first name is a technical reference, her two middle names have more space inspired meaning.
Grimes explained that the “unknown” elements of the dark led to her first middle name. “People fear it but truly it’s the absence of photons. Dark matter is the beautiful mystery of our universe,” she told Vanity Fair. Sidaræl is also a bit of a reference to The Lord of the Rings character Galadriel, and Grimes said that her second middle name is a spelling of “sidereal,” which she said is “the true time of the universe, star time, deep space time, not our relative earth time.”
Before the pair welcomed Y via surrogate in late 2021, Grimes gave birth to X Æ A-Xii in May 2020, and the name naturally sparked much discussion about not only its meaning, but how to pronounce it. Elon explained that the pair pronounce their baby boy’s name “X Ash A Twelve,” on an episode of The Joe Rogan Experience. Grimes had given a breakdown of their son’s name shortly after his name was announced in a tweet. She explained that X was a reference to “unknown variable[s],” while the Æ was meant to represent both “love” and “artificial intelligence.” A-12 was a reference to the CIA program that preceded the aircraft the SR-71, which she said was a “favorite” of her and Elon’s. She also mentioned that the A was also a reference to “Archangel.”
Before starting his relationship with Grimes, Elon was married two women before: Justine Wilson and later he married and divorced actress Talulah Riley twice, and he has five children from his first marriage. Unlike X Æ A-Xii and Y, Elon’s five other children have more traditional names. His eldest are twins Xavier and Griffin, 18, and he also has a set of triplets Kai, Saxon, and Damian, 16. Elon and Justine also had a child Nevada Alexander in 2002, who sadly passed away when he was only 10 weeks old. He didn’t have any children from his relationship with Talulah.