"Promiscuous" (also known as "Promiscuous Girl") is a song recorded by singer Nelly Furtado and Timbaland for Furtado's third album, Loose(2006). Furtado, Timothy "Attitude" Clayton, Timbaland and Danja wrote the song, and Timbaland and Danja produced it. The song lyrics feature a conversation between a man and woman who call each other a "promiscuous" boy or girl.

"Promiscuous" was released as the first single from Loosein North America in early 2006, and as the second single elsewhere in mid-2006 except in Latin America, where the single was released as the third single in late 2006. The song received positive reviews and became Furtado's first number-one single in United States. It won in the Best Pop Song category at the 2006 Billboard Music Awards, was nominated for the Best Pop Collaboration with Vocals Grammy Award at the 49th Annual Grammy Awards and won Single of the Year at the 2007 Juno Awards. The song got a number 3 on the Billboard Year-End Hot 100 singles of 2006. It is the most recent track to top both the Billboard Hot 100 and Billboard Dance Club Play charts simultaneously.

The lyrics of "Promiscuous" describe the two sides of the relationship that the song's protagonist deals with. It was one of the first songs Furtado wrote with labelmate Timothy "Attitude" Clayton. Furtado called their teamwork something she "had never done before" because she saw the writing process as "extremely freeing" because of his different approach and style. Clayton helped Furtado experiment with interpreting the "promiscuous girl" character and the two-sided relationship she is in. Furtado also described that in the process of writing lyrics "we were actually flirting, which is why the song is so playful" and that she and Clayton nicknamed the song "'The BlackBerry Song', because everything we say in the song you could text-message to somebody".

Because of the preponderant musical influence of artists such as Talking Heads, Blondie, Madonna, The Police and Eurythmics, whom producers Timbaland and Danja listened to during the writing of the album, "Promiscuous" takes inspiration from pop music of the 1980s. The sexuality was based on the "strong women in control" of the 1990s, such as Queen Latifah, MC Lyte, Yo-Yo, Salt-N-Pepa and TLC.

A reference to basketball player Steve Nash in the song's lyrics led to speculation that he and Furtado were romantically involved, but both deny the link, with Nash commenting, "I'm flattered that she put me in her song, but I'm completely in love with my wife and two little baby girls". Furtado decided to include him because she and Nash are both from Victoria, British Columbia, and due to frequent citations of basketballers in songs, she decided to "give him the props".

In one of the verses Timbaland introduces himself as Thomas Crown. The Thomas Crown Affairis a film about wealthy businessman who plays a cat-and-mouse/flirting game with an insurance investigator.

Timbaland only performed the song live on special occasions, such as Furtado's appearance on Saturday Night Live, and the 2006 MuchMusic Video Awards. Starting with Furtado's show at the 94th Grey Cup on November 19, 2006, and extending into the Get Loose Tour, Timbaland's part is filled in by Canadian rapper Saukrates.

"Promiscuous" was well received by music critics. Rob Sheffield of Rolling Stoneconsidered it a highlight in Loose. Timbaland's appearance received particular praise, which added Furtado's "high-school musical vocals" over his eighty beats according to Sheffield. Allmusicreviewer Stephen Thomas Erlewine compared it to "vintage Prince", citing "Promiscuous" as a highlight of Furtado's makeover. However, Erlewine believed that no matter how much Furtado sings about sex, she does not sound sexy and does not "generate much carnal heat."

IGN review considered the song "simultaneously annoying and yet catchy beyond belief" and listed as one of Loose's"Definitely Downloads", Pitchfork Media called it "one of the best vocal performances of his [Timbaland's] career", and Billboardcalled the duo of Furtado and Timbaland "a surprisingly good match".

The song was also included in three lists of best songs of 2006: fourth on Blender, sixth at The Village Voice's Pazz & Jop, and 56th on Rolling Stone.

In Canada, the song's music video debuted on MuchMusic's MuchOnDemandafter an interview with Furtado on May 8, 2006. On May 4, 2006, "Promiscuous" debuted inside the top five on the Canadian Singles Chart, and on June 1, it became Furtado's second Canadian number-one single. After descending from the top ten, it reascended to number two after the release of Loose. "Promiscuous" spent twenty-five weeks on the Canadian Singles Chart, but was the year's shortest-running number-one single,but it became one of the biggest selling singles . The song peaked at number two on the BDS Airplay Chart and became one of Furtado's most successful single releases in her home country since "I'm Like a Bird", released in 2000.

In the U.S. "Promiscuous" entered the Hot 100 at number sixty-four, the week's highest debut. It topped the chart for six weeks, from July 8, 2006, and it became Furtado's first U.S. number-one single. The song topped Billboard's Hot Dance Club Play and Pop 100 charts and reached the Hot R&B/Hip-Hop Songs top forty. On the Billboardyear-end chart it was ranked third, the highest placing for a single by a female artist. As of August, 2009, the song has so far sold over 2,504,000 digital downloads in the United States.

"Promiscuous" debuted at number five on the Australian ARIA Charts and peaked at number two in its third week. It was released in Europe on August 18, 2006 and reached number three in the UK. On December 31, 2006 BBC Radio 1 reported that "Promiscuous" was the thirty-eighth highest selling single in the UK in 2006. The single re-entered the UK Singles Chart at number sixty-six in January 2007 because of The Official UK Charts Company's new rules. It made the top ten in most European nations.

In Latin America, the single was released as the official third single, and in some countries the song was leaked to radio (in Peru, Colombia and Mexico). On December 4, 2006, "Promiscuous" won "Best Pop Single of the Year" at the 2006 Billboard Music Awards, beating Daniel Powter's "Bad Day" and Sean Paul's "Temperature". The song was nominated for the "Best Pop Collaboration with Vocals" at the 49th Annual Grammy Awards, losing to Tony Bennett & Stevie Wonder's "For Once in My Life".

The song's music video was directed by Little X and features cameo appearances by Keri Hilson, Bria Myles and Justin Timberlake. It does not follow a storyline and per Furtado's request, focuses on scenes with dancing and flirting because she wanted to recreate the song's indicative vibe, and took the opportunity to film a club video for the first time. Furtado said of the video, "It's that whole dance that goes on. There's that mystery there, the fun, playful sexiness, the verbal Ping-Pong game". Furtado and Timbaland cannot decide whether they want to begin dating or instead flirt with others on the dance floor. Their single performances are intercut with several scenes of a dancing crowd, and the lighting changes between blue, green, red, and yellow colors.

"Promiscuous" premiered on MTV's Total Request Liveon May 3, 2006, where it reached number one after spending twenty-one days on the countdown. After its debut on MuchMusic's Countdown, it ascended to number one for the week of July 28, 2006. At the 2006 MTV Video Music Awards, it was nominated for the Best Dance, Female and Pop Video Awards. The video was parodied by MADtvin a segment entitled "Syphilis Girl"; in the video, Furtado (Nicole Parker) is comically portrayed as having given Timbaland (Jordan Peele) the sexually transmitted disease, as well as on YouTube by the comedic group Train of Thought Sketch Comedy, where the video is parodied by troupe member Kaci and features a puppet version of Timbaland.

These are the formats and track listings of major single releases of "Promiscuous".