Elon Musk and artist Grimes are shedding some light on the meaning of their newborn son's name.
The couple recently announced their first child together is named "X Æ A-12 Musk," which left many questioning the meaning behind it.
Grimes took to Twitter to explain where it comes from. "X" stands for, "the unknown variable," she wrote in a tweet. "Æ" is the musician's, "elven spelling of Ai (love &/or Artificial intelligence)."
"A-12" is the, "precursor to SR-17 (our favorite aircraft)," she added, referencing the A-12 aircraft built in the 60s for the CIA. Musk later clarified that she meant the SR-71 aircraft, not SR-17, in her tweet.
"No weapons, no defenses, just speed," Grimes, whose real name is Claire Elise Boucher, added on the A-12 aircraft. "Great in battle, but non-violent." She wrote that the "A" also references, "Archangel," which she said is her favorite song.
MORE: It's a boy! Elon Musk and recording artist Grimes welcome their 1st child togetherAfter the explanation, many were still left questioning how to pronounce the newborn's name, which neither parent clarified. However, Musk did share a photo holding his son.
He also posted a photo using a funny filter on the newborn.
Musk's mother, Maye Musk, shared a photo of her son with Grimes and expressed her excitement at the arrival of their baby. "Congrats @grimes #ElonMusk. So exciting! Can’t wait to meet him," she captioned the photo. "Ecstatic grandma."
This is Grimes' first child and Musk's seventh child. He had six children with ex-wife Justine Wilson.