Jennifer Aniston is making hair-story once more. The actress, 44, had more than six inches lopped off of her famous head of dirty-blond hair last Thursday; she quietly debuted the sexy-messy, bob-like 'do while running errands in Los Angeles on Monday, Nov. 4, wearing a black top, brown blazer, jeans and shades, and a neutral expression.

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Chatting with Vogue.com before the new photos emerged, Aniston explained that her longtime hairstylist Chris McMillan (who created the now-iconic, hated-by-Aniston "Rachel" cut back in the '90s) did the honors: "Chris McMillan actually chopped all my hair off!" The "We're the Millers" star clarified to the style bible's site that there was no master plan behind the latest cut.

"I actually don't have any red carpets coming up," said Justin Theroux's fiancee. "This is truly just for me!"

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"It's right at my jaw line, maybe a little longer," she mused. "It was kind of spur-of-the-moment," she continued, explaining that the 'do sported by Vogue stylist Lawren Howell, whom Aniston noticed on TV, was the inspiration. And the famously coiffed star is happy with the results. "I don't know, man. I did it! I feel great. I feel lighter. It's simple, it's really simple, that's for sure," she says.

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In an earlier interview with Elle, Aniston also mentioned the cut, and said that her longer tresses had reacted badly to a Brazilian blowout. "My hair went through a phase, this thing called a Brazilian and my hair did not react really well to it," she said of the chemically-intensive straightening treatment.

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"I'm always one of those girls who does a big old chop just to get it really healthy, to repair all the [damage from] hair coloring and stuff like that," Aniston noted to Vogue. "And I just got bored, honestly. It's fun to change it up once in awhile." (See more photos at X17online.)