Elon Musk changes baby's name to X AE A-Xii Musk

Elon Musk and her girlfriend Grimes have decided to change the unusual name of their baby and he will now be known as as X AE A-Xii Musk from the earlier weird name X AE A-12 Musk.

The tweak in the name essentially turns the number 12 into its Roman numeral equivalent, XII.

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

A Twitter user asked Grimes: "Did you change the baby name because of Californian laws ? What is the baby's new name?"

"X Æ A-Xii" wrote the singer in response.

Musk already has five children – Griffin and Xavier and triplets Damian, Saxon and Kai – as well as a son, Nevada, who died as an infant.

Earlier this month, Tesla and SpaceX CEO Musk announced the birth of the baby boy in a post on Twitter, revealing his son was called "X AE A-12 Musk."

"AE" is the Elven spelling of AI, which is shorthand for artificial intelligence and the word for "love" in several languages, including Japanese.

The "A" in the name also represents "Archangel," which Grimes described as her favourite song.

"X, the unknown variable. AE, my elven spelling of AI (love &/or Artificial intelligence), A-12 precursor to SR-17 (our favourite aircraft). No weapons, no defenses, just speed. Great in battle, but non-violent (A=Archangel, my favourite song)," Grimes posted.

Musk posted a photo of the baby through a tattoo/eyelash filter.

"Never too young for some ink," he joked in a follow-up tweet.

Grimes announced that she was pregnant on Instagram in January.

The Canadian singer also revealed she does not want to 'gender' her baby, saying they can "decide their fate and identity' on their own accord.