Grimes Confirms She and Elon Musk Named Their Son X Æ A-12 — And Reveals Meaning Behind the Moniker!

Grimes and Elon Musk welcomed baby boy X Æ A-12 on Monday

Published on May 5, 2020 10:23PM EDT

Grimes is opening up about her newborn son's unique name.

The 32-year-old singer confirmed that she and boyfriend Elon Musk have named their baby boy X Æ A-12 on Tuesday. In a tweet, Grimes — whose birth name is Claire Boucher — broke down the eccentric moniker for fans and explained its meaning down to the last letter.

"X, the unknown variable," the new mom wrote.

"Æ, my elven spelling of Ai (love &/or Artificial intelligence)," Grimes continued, before sharing that a part of her son's name is a nod to the CIA's Lockheed A-12 reconnaissance plane. "A-12 = precursor to SR-17 (our favorite aircraft). No weapons, no defenses, just speed. Great in battle, but non-violent."

Grimes added that the "A" in the name also represents "Archangel" — which she said is her "favorite song" — while the number "12" stood for the Chinese zodiac sign of the rat. (According to the Chinese zodiac, 2020 is the Year of the Metal Rat.)

The baby is the first for Grimes while, Musk, 48, has five sons from a previous marriage. His first son, Nevada, died tragically of SIDS at 10 weeks old in 2002.

Musk posted photos of the little one on both Twitter and Instagram, in response to fans asking for a peek at the newest addition to his family.

In one shot, the sweet baby boy slept while he was swaddled in a receiving blanket, with Musk adding a humorous photo filter that placed face tattoos around the newborn's eyes.

For his second post, the proud father shared a photo of himself holding his son close while in the hospital.

Grimes confirmed she was expecting back in January, sharing her happy news on Instagram weeks after sparking pregnancy speculations with a baby bump photo. Months later, in March, she told Rolling Stone that Musk was the father.

Musk announced the child's birth on Twitter Monday when a fan asked for an update on the baby after the Tesla CEO had previously shared Grimes' due date.

"Mom & baby all good," he wrote on Twitter four hours following a tweet that read: "A few hours away!"

Musk and Grimes were first romantically linked in May 2018.

elon-grimes — Elon Musk and Grimes. Neilson Barnard/Getty

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The two have stayed mostly private about their two-year relationship, though Grimes opened up to Rolling Stone about their bond, saying that she did not grasp the extent to which their romance would come to define her image, especially with fans who did not know her music.

"No one believes me about this, but I just did not understand what I was getting into at all," she said at the time. "Not that I’m mad about it. I just didn’t think it would be a thing. The s— that’s happened with my boyfriend this year has overwritten so much of my life’s work."

"He’s just very good at talking me out of my bulls—," the artist explained."I’ve learned a lot about controlling my state of mind."