Britney told New York radio station Z100 that "Womanizer" is basically saying, "We know what you're up to." Said Spears: "It's about guys cheating on girls. It's a girl anthem. That's why I like it. So hopefully the fans will see it that way too!"

"Womanizer" was a big comeback song for Spears, and her first US #1 since her debut single, "...Baby One More Time," in 1999. In 2004, Spears had to cut short her Onyx Hotel tour due to a knee injury. That year, just months after the tour ended, she married Kevin Federline, a dancer she met on the tour. They had their first child in 2005 and another in 2006, but Spears filed for divorce and started appearing rather unhinged in public, at one point taking a paparazzo's bait and attacking his car with an umbrella. She released the album Blackout in 2007, but was in no condition to promote it, which was clear when she lethargically performed the first single, "Gimme More," at the MTV Video Music Awards.

After a hospital stay, Spears pulled her life together in 2008 and released her sixth album, Circus. She was still commanding a great deal of media attention, so all ears were on the first single, "Womanizer." It was just what she needed: a fun, uptempo hit with modern production and a sleek video. Britney was back.

This was written and produced by two members of the Atlanta crew The Outsyders: Nikesha Briscoe and Rafael Akinyemi. It was the first major writing and producing credit for The Outsyders; they later did arrangements on Kelly Rowland's track "Keep It Between Us."

In this song, Spears warns her cheating man:

You say I'm crazy
I got your crazy

During her public implosion, Spears really did seem crazy, or at least unable to handle the stress of her divorce compounded by substance abuse. In January 2008, she was twice committed to a psychiatric institution, the second time at the behest of her family. These lines harness the energy of her instability, letting the guy in the song know that she is indeed crazy, and he better watch out.

Spears' vocal is saturated with Auto-Tune, which was the sound of 2008. The robotic timbre of her voice meshes with the track, which is filled with EDM beats.

The music video played a huge role in this song's success. Directed by Joseph Kahn, who previously helmed her clips for "Stronger" and "Toxic," it opens with Spears at home with her boyfriend, played by Brandon Stoughton. She then plays the role of three different vixen who seduce him: a businesswoman, a vampy waitress, and a chauffeur. When he returns home, she reveals herself to be the embodiment of all these women, and takes him down his transgressions.

The video was huge on MTV, and was the most-streamed music video of 2008 on MTV.com. In 2009, the "director's cut," with some shots of Spears strategically nude, showed up on YouTube. Last we checked, it had over 250 million views.

We counted 41 repetitions of the word "womanizer" in this song, including nine in each chorus.

Outside of the USA, this song entered the Top 10 in every European country in which it was released, topping the charts in Belgium, Denmark, Finland, France, Norway and Sweden. It also reached #1 in Canada and the World Singles Top 40.

One week after T.I.'s "Live Your Life" vaulted from #80 to #1 on the Hot 100, "Womanizer" made another record-breaking jump. On the chart dated October 17, 2008, it debuted at #96. The following week, it went to #1, making the biggest-ever jump to the top position.

This song's first-week download sales of 286,000 was the biggest opening-week tally by a female artist to date. However it was unable to beat "Live Your Life's" record-breaking debut total of 334,000 digital downloads. (The female on that track, Rihanna, was not credited as the main artist.) The song's first-week digital sales record was broken by Taylor Swift's "Today Was a Fairytale," which moved 325,000 digital sales on the first February chart of 2010.

A number of high-profile artists recorded cover versions of this song. First it was Lily Allen, then the All-American Rejects. Spears' hit "Toxic" also inspired a series of cover versions in various styles. >>

Parts of the music video where Spears plays a waitress were shot at Elevate Lounge, a club located within the Takami Sushi & Robata restaurant in Los Angeles. Britney was also a waitress in her 1999 video for "(You Drive Me) Crazy."