Mystery solved! Elon Musk and Grimes' baby's name has been a hot topic of curiosity since the little boy was welcomed into the world this week. The Tesla CEO recently shared his newborn's name on Twitter and people immediately had questions. Luckily, he finally explained the pronunciation in a recent interview.

The couple of two years welcomed X Æ A-12 on May 4, with Musk sharing updates on Twitter to excited fans.

The 48-year-old, known for his interesting sense of humour, quickly released a first look at the bundle of joy. A fake tattoo filter over the photo had him looking like Post Malone and the infant made his mark on the world within hours of his birth.

That same day, both parents tweeted out the name of their son but didn't attach a pronunciation guide which left many confused.

A recent interview on The Joe Rogan Experience podcast had Musk explain how to pronounce baby X Æ A-12's name.

"It's just X, the letter X. And then the Æ is pronounced ash," Musk explained, crediting Grimes for coming up with most of the name. "And then A-12 is my contribution. Archangel 12, the precursor to the SR-71, coolest plane ever."

You can hear Musk explain the name at the 46-second point below.

The new mom confirmed her son's name the day after his birth and explained the meaning behind each letter.

"X, the unknown variable. 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)," the singer tweeted.

Shortly after, Musk replied back correcting his partner, writing, "SR-71, but yes".

This is 32-year-old Grimes' first child and Musk's seventh son. The father of six shares a set of triplets and twins with his former wife, Justine Wilson. 

The couple's relationship timeline goes back to 2018 when they met on Twitter over a shared interest in artificial intelligence. The Vancouver-born singer got the attention of Musk when she made a joke about Rococo Basilisk.

Their red carpet debut came in May 2018 and was followed by a series of hot and cold events where they unfollowed and refollowed each other on social media.

In January, Grimes shared that she was expecting a baby and confirmed in March that Musk is the father.

NOW WATCH Elon Musk Corrects Grimes As She Misspells An Aircraft Their Son Was Named After (VIDEO)