The 18-year-old Australian television personality said in an interview Thursday with E! News that Terri, 52, is "just friends" with the New Zealand star.
"My dad is still very much my mum's soulmate," Bindi said of late dad Steve Irwin. "Mum always says they'll always be married. To her, they're always going to be together. In this life and the next, they're a couple and a team."
"We do love Russell, but mum and Russell aren't actually in love," she insisted. "Russell is a wonderful wildlife warrior. He was a dear friend of dad's and now a dear friend of ours. He feels like family to us, but mum and Russell? Just friends, for sure."
Terri and Russell have been linked off and on since Steve died at age 44 in 2006. Terri said in the September issue of Australian Women's Weekly that she hasn't dated since The Crocodile Hunter star passed.
"I haven't gone on a single date since Steve died," she told the magazine. "If I hadn't met Steve, I probably would have never married because I wasn't looking for love when I met him."
Bindi herself has been dating American wakeboarder Chandler Powell since 2015. She denied in the E! interview that she and Powell are living together, but said the 20-year-old is now splitting his time between Florida and Australia.
"We are doing very, very well. I'm so lucky," the star gushed. "Chandler is wonderful. I'm very blessed."