Some nicknames are embarrassing and others are just plain weird. But Hollywood actress Charlize Theron's nickname is both and we really need to know how she came by it.

The South African was given the moniker by her former co-star Jeremy Renner who calls her "Ass-Nuts" whenever the two are together.

The 34-year-old actress met Jeremy when the pair starred in the 2005 movie North Country and have apparently become firm friends.

Charlize isn't telling what it means or indeed where it came from but she did reveal that alcohol was a factor.

She told E! that it all came about after the cast popped out for a few drinks, saying: "I can't tell you what transpired, but let me just say I found a friend for life in Jeremy, and he has ever since then referred to me as Ass-Nuts."

"I wish that was a joke, but it's true," she added.

And it's left us with various weird and not always wonderful thoughts running through our minds.

Charlize may have regretted making her nickname known. But then celebs do say the strangest things...