On Monday, after the Tesla CEO announced the birth of his child with the Canadian singer, a fan tweeted, “We need the name we literally need it.”

Musk, 48, responded, “X Æ A-12 Musk,” with no explanation. He also shared two photos of the newborn — one with a filter of tattoos on his face.

One person on Twitter appeared to guess the pronunciation correctly because the tech guru liked their tweet, which said, “X Ash Archangel?”

The tweet also showed a screenshot of a Wikipedia page that explained Æ is a ligature named ash. The A-12 is thought to be in reference to the CIA aircraft Lockheed A-12, which was codenamed Archangel.

Another person speculated on Twitter that the name is Xavier, writing, “So I feel like a genius for breaking the code to Elon Musk and Grimes baby boys name. It’s Xavier. X-a, then 1 in mandarin is ‘yee’ and 2 is ‘er.’ Thank you for listening to me, a stable genius.”

However, Musk already has a son named Xavier. He has five sons from his previous marriage to author Justine Wilson, including twins Xavier and Griffin, and triplets Damian, Saxon and Kai.

X Æ A-12 is Grimes’ first child. The 32-year-old singer has not commented on her son’s name on social media.

It is unclear whether Musk was joking about the name or whether that is their son’s actual name. However, public figures naming their child unusual monikers is not out of the realm of possibility in Hollywood.

Musk and Grimes’ reps did not immediately return our requests for comment.