Jost told Meyers about his mom's reaction to the baby name Cosmo, "She was like 'OK, interesting. Because I was reading that there's also a name Cosimo with an 'I,' so that could also be an option. Maybe Cosimo, that's his real name, but then you can call him still Cosmo'" (via E! Online).
Another suggestion she offered? Cosmos, who is a patron saint according to Jost's mom. The saint is actually named Cosmas, according to Britannica, but no matter, because Johansson and Jost are not looking to change their son's name.
The good news is that eventually, the movie star's mother-in-law accepted that her grandson's name is going to be Cosmo, with Jost explaining to Meyers, "So then she would call, and she would say, 'I met someone—they said their uncle's name is Cosmo. So it is OK.'"
Meanwhile, according to Nameberry, Cosmo means "order, beauty" and is of Greek origin. The site notes Cosmo was Kramer's first name on the show "Seinfeld," so it must be cool!
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