(CNN) -- If you're going to name your kid after a wild animal, at least have a good reason.

Kate Winslet, who welcomed son Bear Blaze with husband Ned Rocknroll last December, has assured "Ellen's" Ellen DeGeneres that yes, there's a purpose for the kid's unique signature.

Bear Blaze is the 38-year-old star's third child -- she had daughter Mia, 13, and son Joe, 10, with prior husbands Jim Threapleton and Sam Mendes, respectively -- and this time around she had baby names on the brain.

"When I was pregnant with Mia and I was pregnant with Joe, I didn't name them before they came out because I always felt like I just have to see them and see who they're going to be," Winslet said. "But of course this time around, there's Mia and Joe and the whole pregnancy's about what are we going to call the baby. ... They were very much included, and we settled on Bear quite early on."

The reason she loved the name is because a friend of hers was nicknamed Bear, "and I just had always really loved it," the "Divergent" actress said. "He was very much a bear, he was everybody's shoulder to cry on, he was a big bear hug. He was just this great figure in my life."

And to pick Bear's middle name, she and her husband Ned wanted something that represented their bond.

"Bear's second name is Blaze because my husband and I met in a house fire basically," the actress continued, referring to the fire that consumed billionaire Richard Branson's Caribbean home while she was staying there in 2011.

"The house burnt down and we survived, but we wanted something of the fire, and so Blaze was the name that we came up with."

Bear Blaze may be uncommon, but Winslet didn't want to be creative with the infant's last name. While her husband enjoys the last name Rocknroll, an eccentric moniker he adopted before he met and married the actress, it's pretty clear she doesn't like it.

When DeGeneres asked why Winslet's youngest son isn't taking his father's last name, she paused before responding with a laugh, "Why do you think, Ellen?"

Instead, he'll be known as Bear Blaze Winslet.