Nicole Kidman Reveals 'Babygirl' Is Keith Urban's Nickname for Her (and He Has a Neck Tattoo of It Too!)

"He’s like, 'No, I still have total rights over babygirl!'" she said

Nicole Kidman was already Keith Urban's "babygirl" long before she signed up for the movie titled with the same nickname.

The Oscar winner, who next stars in the erotic drama Babygirl, revealed to W Magazine for The Art Issue that her country-star husband, 57, calls her the nickname already and even put it in ink.

"He actually has 'babygirl' tattooed on the back of his neck,” said Kidman, 57, adding, "Keith’s not allowed to call anyone else babygirl. But now, because of the film, it’s taken on a different meaning. So he’s like, ‘No, I still have total rights over babygirl!’ ”

Kidman married Urban in 2006 and they share two daughters, Sunday, 16, and Faith, 13.

The actress added she isn't aware if Babygirl writer-director Halina Reijn even knows about the nickname coincidence. “I don’t know if Halina knows that, but it’s all part of this sprinkling of fairy dust that happens," she said.

Related: Nicole Kidman Reveals Husband Keith Urban's Reaction When They Binge-Watched The Perfect Couple Together

In Babygirl, Kidman stars as a powerful CEO named Romy who risks her career and family to engage in a kinky affair with an intern, played by Harris Dickinson, 28. The film also stars Antonio Banderas, and in the trailer, Dickinson's character calls Romy a "good girl" and later says, "You're my babygirl."

Kidman recalled to W Magazine how the project came to her attention. "I knew about Halina Reijn, and I heard she was directing a film called Babygirl. I was in Australia and I called Halina, and we didn’t get off the phone for almost two hours. From that point on, we were doing the film together."

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“Playing this character didn’t scare me at all,” said Kidman, who won best actress at the Venice Film Festival for her performance. “It captivated me. It pulled me in. I wanted to make sure that I fulfilled Halina’s vision."

"But on the first day," she added, "I started to go, ‘This is going to be very exposing.’ And there were different points when it was like, ‘I don’t want to be looked at, touched in any way anymore. No more, no more, no more.’ ”

Babygirl is in theaters Dec. 25.