Elon Musk and Grimes made headlines in May 2020 with the birth of their son, not only because of the celebrity status of his parents but also due to his highly unusual name: X Æ A-12 Musk. The name instantly sparked curiosity and confusion, leading many to question its legality, pronunciation, and meaning.

The Tesla and SpaceX CEO, Elon Musk, first announced the news on Twitter when a follower asked about Grimes’s labor. He tweeted that she was “a few hours away!” and later confirmed, “Mom & baby all good.” However, the real surprise came when he revealed the baby’s name: X Æ A-12 Musk.

At first, people assumed Musk might be joking, given his history of posting memes and cryptic tweets. However, it was soon confirmed that the name was indeed real—a name that would intrigue, perplex, and be discussed for years to come.

Name Change and Legal Hurdles

Soon after the announcement, concerns were raised about the legality of the name under California state law, which only permits the use of the 26 letters of the English alphabet for birth certificates. Since “Æ” and “12” are not standard alphabetic characters, Musk and Grimes had to modify it slightly. They changed it to X Æ A-Xii, replacing “12” with the Roman numeral equivalent “Xii”.

Grimes confirmed the change on Instagram, saying: “Roman numerals. Looks better tbh.”

The Meaning Behind the Name

Grimes later explained the name’s significance:

  • X represents “the unknown variable,” a common mathematical symbol.
  • Æ is an Elven spelling of “AI,” which stands for “artificial intelligence” and also means “love” in several languages.
  • A-12 was a reference to the Archangel 12, a precursor to the SR-71 Blackbird reconnaissance aircraft, which Musk and Grimes admire for its speed and performance.
  • A also stands for “Archangel,” which is the title of a song by the artist Burial—Grimes has mentioned this as her favorite song.

How Do You Pronounce X Æ A-Xii?

Even Musk and Grimes have slightly different takes on how to pronounce their son’s name:

Grimes’s version:

“It’s just X, like the letter X. Then AI. Like how you said the letter A, then I.”

Musk’s version:

“I mean, it’s just X, the letter X. And then, the Æ is like ‘Ash’… and then, A-12 is my contribution.” He shared this explanation during an interview with Joe Rogan.

Unique But Not Unprecedented

While X Æ A-Xii might be one of the most unusual baby names in modern times, it’s not entirely without precedent.

Celebrities have long been known for choosing unconventional names for their children, from Apple (Gwyneth Paltrow and Chris Martin’s daughter) to North (Kim Kardashian and Kanye West’s daughter).

However, Musk and Grimes took it to a new level by incorporating elements of mathematics, technology, and aeronautics into their child’s name.

What Do They Call Him for Short?

In casual conversations, Musk has referred to his son as “X,” a simple and practical nickname that avoids the complexities of his full name. Given the unconventional combination of letters, symbols, and numbers in X Æ A-Xii, shortening it to just “X” makes it much easier for everyday use, both at home and in public.