Aniston, 42, is best known for her work in the TV sitcom "Friends," and in light-hearted romantic fare like "She's the One," "Picture Perfect," "Bruce Almighty" and "Along Came Polly."
Her new movie, co-starring Jason Sudeikis, Jason Bateman, Charlie Day, Kevin Spacey, Jamie Foxx and Colin Farrell, casts her as a not-so-nice dentist with a potty mouth and a penchant for sexually harassing her assistant.
"I know I had no hesitation at all [about taking the role,]" Aniston told reporters at a recent news conference in New York.
"It was on the page. I was just doing my job," she said of her character's salty speech. "There was nothing that happened that [director Seth Gordon] wasn't so tickled and excited about. After every take, he was like, 'The raunchier, the better.' So, it was pretty easy."
Asked if she signed on to play this character to get past her "America's Sweetheart" image, Aniston replied, "I didn't take the role so I could rid myself of that title."
"There are so many different 'American Sweethearts.' I just took it because I loved it and thought it would be a fun challenge and fun for me to step out of what people usually like to see me play," she added. "That's a label; you're branded. There's always going to be something attached to you. But, no, I wasn't [trying to challenge that title.]"
So, did she do any research to prepare for the part?
"No. I did go to the dentist right beforehand, though," she quipped. "To see how they hold the tools, then the rest was easy."
"Horrible Bosses" hits U.S. theaters Friday. It is rated R.