Charlize Theron's daughters won't let her use their favourite slang words.

The 49-year-old actress - who has adopted kids Jackson, 12, and nine-year-old August - think she is "too old" for certain popular terms, while she is "not allowed" to use other phrases because they have gone out of fashion.

Walking the red carpet in a fishnet Givenchy outfit at the Los Angeles premiere of her latest movie The Old Guard 2, Charlize told Extra of her look: "August gave it a thumbs-up."

Host Terri Seymour then asked: "What do they say? Would it be 'snatched'? Do we say you're looking 'snatched'?"

Charlize admitted: "Apparently, I'm not allowed to say it. There's so many things I'm just not allowed to say anymore. I'm still learning my way.

"'Rizz' is something that I can't say. Nobody says it, apparently. There's a lot of like, 'You can't say that because you're old,' but she was like 'Nobody even says that anymore,' so every day is an education. All of it.

"Things change so fast… I wouldn't go by my understanding of this very intricate language of the Gen Alphas and Zs."

And while Charlize "loved" her retro hairstyle in The Old Guard 2, she recently admitted her kids were horrified by her mullet.

Speaking on Late Night with Seth Meyers, she said: "I have two girls, and they're very, very... they're mostly very girly. And they think of me as a princess. And they want Mom to look like a princess.

"But they came back from school. I was in my bathroom and I was getting it cut and it had already been coloured. And I just remember looking over and they both came into the room really excited, and then they just both froze. And they just went... and one started crying.

"One literally started bawling their eyes out. And I had to actually sit down with her and say, 'We all get to be who we want to be. And right now, Mom wants to wear a mullet.' I don't tell you what to do with your hair."

Impersonating one of her children, Charlize added: "I still don't like it."

The Mad Max: Fury Road actress revealed last month that her children are unimpressed by her Hollywood career.

During an appearance on Jimmy Kimmel Live!, Theron quipped: "My children have zero respect for me.

"It's just unbelievable, I feel like I'm pretty humble, but every once in a while I'm like, 'There's a f****** Oscar right there.' They are so not impressed with me."

Charlize recalled an incident when her youngest child unflatteringly compared her with Tom Cruise.

She explained: "I was picking up my youngest from dance yesterday and we drove past the new Mission Impossible poster where Tom Cruise is hanging onto some yellow plane, and he just looks really cool.

"My kids were with me when I shot Old Guard 2 and I worked on this incredibly intricate sequence where we brought in this amazing helicopter pilot, Fred North, and we were gonna choreograph me fighting helicopters and jumping on this real helicopter and hanging off. Shooting 99 per cent of it on a real helicopter as it's trying to shake me off like a rag doll.

"We took like two weeks to shoot this sequence and I was like, 'Wow, I just did that, that's really amazing.' And my child yesterday just looked at this poster of Tom Cruise and went, 'It's weird, he looks so much cooler than you did when you were hanging off the helicopter.'

"I was just like, 'I hung off the helicopter, [can I have] some credit?'"