Robert Downey Jr. and Wife Susan Welcome Son Exton

Lester Cohen/WireImage
Lester Cohen/WireImage

Move over, Apple, Suri, Bronx, and Blue Ivy — here comes Exton Elias. That's the unusual moniker Robert Downey Jr. and his wife, Susan, have given their newborn son, who was born on Tuesday morning in Los Angeles, clocking in at 7 pounds, 5 ounces and 20 inches long. "Everyone is healthy and they couldn't be happier," a friend of the couple tells People.

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Although the "Sherlock Holmes" actor, 46, accidentally spilled the beans about the baby's sex in December, he stopped short of also revealing the name they had chosen for their little one. "If I told you the name, then [my wife] would lop off my head with a machete," Downey joked — or at least we hope it was a joke.

The new parents have yet to explain their decision to name their first child together Exton, but the word is typically associated with the city in Pennsylvania. Coincidentally (or maybe not), RDJ and his first wife, Deborah Falconer, also named their now-18-year-old son after a location -- Indio, a Southern California city that happens to be home to the Coachella Music Festival.

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"Place names and surnames with an 'x' inside them have been soaring for boys," Laura Wattenberg (http://babynamewizard.com) tells omg!. "It's like a little super-power boost inside an otherwise unassuming name. Jaxon, Braxton, and Paxton are the leaders of that pack, and many others, like Maxton and Lexington are rising. Exton is a little surprising, though, because it's not especially nickname-friendly. Ex, with its suggestion of ex-wives and ex-boyfriends, isn't likely."

As for baby Exton's middle name, Elias, perhaps it's a nod to New York Giants star quarterback, Eli Manning, who led his team to a Super Bowl win on Sunday. After all, dad Robert is a NYC native.

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Exton may seem like a peculiar choice for a baby name -- but not in Hollywood, home to some of the biggest head-scratchers and tongue-twisters. Here's a sampling:

Audio Science, the son of actress Shannyn Sossamon and kickboxing instructor Dallas Clayton
Moxie Crimefighter, the daughter of Penn Jillette and his wife, Emily
Pilot Inspektor, the son of Jason Lee and his wife, Beth
Kal-El, the son of Nicolas Cage and his wife, Alice Kim
Speck Wildhorse, the son of John Mellencamp and Elaine Irwin
Sparrow James Midnight, the son of Nicole Richie and Joel Madden
Bluebell Madonna, the daughter of Spice Girl Geri Halliwell and Sacha Gervasi
Banjo Patrick, the son of Rachel Griffith and Andrew Taylor
Kyd Miller, the son of David Duchovny and Tea Leoni
Elijah Bob Patricius Guggi Q, the son of Bono and Ali Hewson
Nakoa-Wolf Manakauapo Namakaeha, the son of Lisa Bonet and Jason Momoa
Daisy Boo and Poppy Honey, the daughters of Jamie Oliver and wife Jools Norton
Reignbeau, the daughter of Ving Rhames and Deborah Reed
Jermajesty, the son of Jermaine Jackson and Alejandra
Diva Thin Muffin Pigeen and Moon Unit, the daughters of Frank Zappa (who also named his sons Dweezil and Ahmet)

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