Last March, singer Grimes announced that she and her former partner Elon Musk had welcomed their second child together. The couple gave their little one an unusual name and while Grimes later revealed they might be changing it, she didn’t explain further… until now.

When announcing she had a second child, the “Shinigami Eyes” singer shared she named her daughter Exa Dark Sideræl and would use the nickname “Y.” The singer explained the choice behind the name sharing at the time that Exa referred to the supercomputing term, exaFLOPS and the name Dark represented “the unknown.” Grimes further explained this sharing “People fear it but truly it’s the absence of photons. Dark matter is the beautiful mystery of our universe.” Sideræl, is pronounced sigh-deer-ee-el, was described by Grimes as “a more elven” spelling of sidereal, which she defined as “the true time of the universe, star time, deep space-time, not our relative earth time.” There is double meaning for the name as it is a representation of Grimes’ favorite Lord of the Rings character, Galadriel, who “chooses to abdicate the ring.”

The singer has recently addressed the current name of her daughter. Grimes shared two side-by-side images one of herself and the other of her daughter, where each appeared to be dressed similarly in red onesies with green hair. She captioned the post “Y C.” A Grimes fan account replied to the tweet writing, “omg baby sailor mars hiiii,” and the “Player of Games” singer took the opportunity to address her daughter’s current name. She tweeted, “She’s Y now, or “Why?” or just “?” (But the government won’t recognize that). curiosity, the eternal question, .. and such.” Given the meaning behind her new explanation, it does tie into the meanings of Y’s original name.

Grimes and Elon are no strangers to being unable to use their first-choice names for their children due to government restrictions. The couple welcomed a son in 2020 and named him X Æ A-12. However, the California state constitution only allows names to use the 26 alphabetical characters of the English language. The couple ultimately changed the 12 to Roman numerals, making their son’s name X Æ A-Xii. Their son goes by the nickname X.

With these changes and the given nicknames, the couple’s children are X and Y. Perhaps if they choose to expand their family, their third child together with have the name Z. We’ll see!

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Kate Fann (she/her) is the BabyNames.com celebrity blogger, as well as an established content writer, aspiring author, and social media expert. She has been featured in online publications such as Bolde, ManoByte, Medium, The Social Observer, and more. Kate has ghostwritten numerous romance novels and is currently working on publishing her own works in the Young Adult genre.

Kate lives in East Tennessee with her husband Casey and her two sons, Quinn and Noah. When she's not writing or scrolling Instagram, Kate can be found tasting delicious wines, playing with make-up, baking yummy treats, or hiking the beautiful Smoky Mountains.