Cher (; born Cherilyn Sarkisian; May 20, 1946) is an American singer, actress and television personality. Often referred to by the media as the "Goddess of Pop", she has been described as embodying female autonomy in a male-dominated industry. Cher is known for her distinctive contralto singing voice and for having worked in numerous areas of entertainment, as well as adopting a variety of styles and appearances throughout her six-decade-long career. Cher gained popularity in 1965 as one half of the folk rock husband-wife duo Sonny & Cher after their song "I Got You Babe" peaked at number one on the US and UK charts. Together they sold 40 million records worldwide. Her solo career was established during the same time, with the top-ten singles "Bang Bang (My Baby Shot Me Down)" and "You Better Sit Down Kids". She became a television personality in the 1970s with her CBS shows; first The Sonny & Cher Comedy Hour, watched by over 30 million viewers weekly during its three-year run, and then the namesake Cher. She emerged as a fashion trendsetter by wearing elaborate outfits on her television shows. While working on television, Cher released the US Billboard Hot 100 number-one singles "Gypsys, Tramps & Thieves", "Half-Breed", and "Dark Lady", becoming the female artist with the most number-one singles in United States history at the time. After her divorce from Sonny Bono in 1975, she released the disco album Take Me Home (1979) and earned $300,000 a week for her 1979–1982 concert residency in Las Vegas.

In 1982, Cher made her Broadway debut in the play Come Back to the 5 & Dime, Jimmy Dean, Jimmy Dean and starred in its film adaptation. She subsequently garnered critical acclaim for her performances in films such as Silkwood (1983), Mask (1985), The Witches of Eastwick (1987), and Moonstruck (1987), the last of which won her the Academy Award for Best Actress. She then revived her music career by recording the rock-inflected albums Cher (1987), Heart of Stone (1989), and Love Hurts (1991), all of which yielded successful singles such as "I Found Someone", "If I Could Turn Back Time", and "Love and Understanding". Cher contributed to the soundtrack for her next film, Mermaids (1990), which spawned the UK number-one single "The Shoop Shoop Song (It's in His Kiss)". She made her directorial debut with a segment in the abortion-themed anthology If These Walls Could Talk (1996).

Cher reached a new commercial peak in 1998 with the dance-pop album Believe, whose title track topped the Billboard Year-End Hot 100 singles of 1999 and became the biggest-selling single of all time by a female artist in the UK. It features pioneering use of Auto-Tune to distort her vocals, known as the "Cher effect". Her 2002–2005 Living Proof: The Farewell Tour became one of the highest-grossing concert tours of all time, earning $250 million. In 2008, she signed a $60 million deal to headline the Colosseum at Caesars Palace in Las Vegas for three years. During the 2010s, she landed starring roles in the films Burlesque (2010) and Mamma Mia! Here We Go Again (2018) and released studio albums Closer to the Truth (2013) and Dancing Queen (2018), both of which debuted at number three on the Billboard 200.

Having sold 100 million records, Cher is one of the world's best-selling music artists. Her achievements include a Grammy Award, an Emmy Award, an Academy Award, three Golden Globe Awards, a Cannes Film Festival award, the Billboard Icon Award, and awards from the Kennedy Center Honors and the Council of Fashion Designers of America. She is the only artist to date to have a number-one single on a Billboard chart in six consecutive decades, from the 1960s to the 2010s. Aside from music and acting, she is noted for her political views, social media presence, philanthropic endeavors, and social activism, including LGBT rights and HIV/AIDS prevention.