Heidi Klum and Seal welcomed their baby daughter, Lou Sulola Samuel, on Friday in Los Angeles.

What does her name mean?

"Lou represents a combination of two growing trends: nicknames on the birth certificate and boys' names for girls," Linda Rosenkrantz, who cowrote Baby Name Bible and runs NameBerry.com, tells Usmagazine.com. 

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"Although Lou has always been used as a short name for Louise and Louella, it has rarely been heard as a full first name for a girl," Rosenkrantz explains. 

The author goes on, "The nickname trend was seen more recently with Charlie Sheen's twins Max and Bob" instead of the more formal Maxwell and Robert.

More examples of shortened names are Hank Azaria's son, Hal, and Adam Sandler's daughter, Sunny.

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Baby Name Bible coauthor Pamela Satran points out that Lou "is one of the most popular and fashionable girls' names in France these days.

"Chic Parisians use the name just as Lou. The ironic thing is that in the U.S. it still has kind of has a backwoods country feel -- Emmy Lou, Lou-Ann -- rather than a sophisticated European one," she goes on.

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Satran adds, "But it does feel sleek and chic yet down-to-earth and real, much like Heidi and Seal!"

The baby's middle name, Sulola, has its roots in Seal's native Nigeria. Lou's brothers also have African middle names: Henry Gunther Ademola Dashtu Samuel, 4, and Johan Riley Fyodor Taiwo Samuel, 2. (Klum, 36, is also mother to Leni Klum, 5, with ex Flavio Briatore, an Italian businessman.)

Seal, 46, confirmed Lou's birth to Us in a statement Monday night.

"From the moment she looked into both of our eyes it was endless love at first sight," he said. "She is beautiful beyond words and we are happy that she chose us to watch her grow over the coming years."

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