If you flicked through a bumper book of baby names, chances are you wouldn't find many which include letters, numbers and punctuation.
Which is probably why Elon Musk and Grimes decided to combine all of these characters when coming up with a moniker for their firstborn - you know, to be original and all of that.
And after nine months of brainstorming a name for their new baby, the pair presented their son 'X Æ A-12 Musk' to the world in May 2020.
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Most people didn't have a clue about how to pronounce it, let alone what it meant...so it's probably a good job that it only stuck around for a few weeks.
Musk first announced the birth of his seventh child in a post shared on X on 5 May, 2020, before going on to reveal the tot's unique name.
Grimes, 36, then provided a bit more context about why they had decided to name their baby X Æ A-12 in a post shared on the social media platform the following day.
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Breaking it down for her baffled fans, the Canadian musician wrote: "X, the unknown variable. Æ, my elven spelling of AI (love &/or Artificial Intelligence).
"A-12 = precursor to SR-17 (our favourite aircraft). No weapons, no defences, just speed. Great in battle, but non-violent + (A=Archangel, my favourite song) (metal rat)."
In hindsight, that probably left people even more confused than they were in the first place.
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Podcaster Joe Rogan then did us all a solid by asking Musk to explain the origin of X Æ A-12 further, as he admitted he thought it was some kind of 'placeholder'.
During the episode which aired in May 2020, the Tesla boss, 53, said: "First of all, [Grimes] is the one that, actually, mostly, came up with the name. She’s great at names. I mean it’s just X, the letter X. Um, and then, the Æ is, like, pronounced ‘Ash’. And then, A-12, A-12 is my contribution."
"Archangel 12, the precursor to the SR-71, is the coolest plane ever," the billionaire added.
But despite spending a significant amount of time explaining their son's name, the parents were forced to bin it off before the youngster had even turned a month old as unfortunately for them, the name X Æ A-12 did not comply with the law in California.
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According to the state constitution, names must only 'use the 26 alphabetical letters of the English language'...and you can see how Musk and Grimes fell foul of that.
But the new parents came up with a crafty way to get around the issue.
Still keen to keep their son's quirky name, the pair got rid of the numbers for Roman numerals and instead changed the moniker to X Æ A-Xii - with his first name being X, middle name AE A-XII and surname Musk.
After announcing the news, Grimes said: "Roman numerals. Looks better tbh," before clarifying that one dash is 'allowed'.
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At the time, family attorney David Glass explained the rules about names in California.
He told People: "Anything that has to be filed with the state, they have a handbook that includes this particular sentence that says the birth certificate must be filled out 'using the 26 alphabetical letters of the English language'.
"I don't think you can say [X Æ A-12] is illegal -it just won't be accepted.
"So your child won't have an official name and won't have a birth certificate and you can't get a social security number until you have a birth certificate and on down the line.
"They have an opportunity to appeal the rejection of the birth certificate application but it's unlikely that it will be granted because, again...California has been struggling with using symbols."
Musk and Grimes went to welcome another two children together - three-year-old Exa Dark Sideræl Musk, who's name was also changed, and two-year-old Techno Mechanicus, who is known as Tau.
But they parted ways romantically in around 2021 and were locked in a custody battle over their three children, which has since reportedly been resolved, according to Business Insider.