Elon Musk and Grimes were forced to change their son’s name by law

As far as original baby names go, Grimes and Elon Musk may just take the biscuit for their firstborn's imaginative, if a little complex, full moniker.

The former couple had their first son in May 2020 after dating for two years.

The Canadian musician (whose real name is Claire Elise Boucher) and the billionaire tech mogul really pulled all the stops to ensure he had a name like no other.

Unfortunately, Californian laws didn't allow them to keep the original suggestion so the pair had to skirt the rules and slightly tweak the name of their little bundle of joy to comply with state law.

The baby's name was X Æ A-12, which is pronounced 'Ex Ash A Twelve'. Grimes took the time to explain her reasoning for picking all the different elements in her son's name.

In a tweet posted at the time, the singer said that she and Musk included X for the unknown variable and A-12 after their favourite aircraft.

"Æ is the the Elven spelling of Ai (love &/or Artificial intelligence)," she wrote.

"A-12 = precursor to SR-17 (our favourite aircraft). No weapons, no defences, just speed. Great in battle, but non-violent. (A=Archangel, my favorite song)."

It was their homage to the high-altitude plane which made the name invalid according to California law.

A few weeks after their son's birth, Grimes confirmed on her Instagram account that she and Musk had to get rid of the Arabic numbers.

While the A-12 had to go, the parents decided to use Roman numerals instead, so the baby's official name was changed into X Æ A-Xii.

When quizzed by fans about the new name, Grimes said she liked it better with Roman numbers instead of the Arabic they originally used.

"Roman numerals. Looks better tbh," she said.

Grimes also clarified that one dash is 'allowed'.

At the time, family attorney David Glass explained why the original, out-there moniker, though technically legal, wasn't likely to be accepted by the state.

"In California, you can only use the 26 characters of the English language in your baby name," he told People in May 2020.

"Thus, you can't have numbers, Roman numerals, accents, umlauts or other symbols or emojis. Although an apostrophe, for a name like 'O'Connor,' is acceptable.

"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."