"X, the unknown variable," she wrote on social media. "Æ, my elven spelling of Ai (love &/or Artificial intelligence) A-12 = precursor to SR-17 (our favorite aircraft). No weapons, no defenses, just

"X, the unknown variable," she wrote on social media. "Æ, my elven spelling of Ai (love &/or Artificial intelligence) A-12 = precursor to SR-17 (our favorite aircraft). No weapons, no defenses, just speed. Great in battle, but non-violent. A=Archangel, my favorite song." She concluded the lengthy explanation with a rat and sword emoji, adding, "Metal rat."

Little did she know, her explanation featured a typo, which the Tesla mogul corrected: "SR-71, but yes." Grimes responded, "I am recovering from surgery and barely alive so may my typos b forgiven but, da--it. That was meant to be profound."

As for how "X Æ A-12" is pronounced, Musk later said, "So, it's just X, the letter X, and then the Æ is pronounced Ash." During his interview on The Joe Rogan Experience, he revealed that Grimes "mostly came up with the name," adding, "She's brilliant."