A catsuit is a one-piece form-fitting garment that covers the torso and the legs, and frequently the arms.^[1] They are usually made from stretchable material, such as lycra, chiffon, spandex (after 1959), latex, or velour, but may use less elastic materials, such as leather or PVC. Catsuits frequently close by means of a zipper at the front or back. A catsuit is regarded as outerwear, but not normally street wear. Catsuits are also used for sexualization or other types of sexuality.

Catsuits were occasionally worn as a fashion item at various times from the 1960s to the 1990s. During the 1970s and 1980s, they were worn for aerobics and disco dancing. Around 1980, disco dance catsuits briefly became a street fashion item in the United Kingdom.

Athletes in sports such as speed skating, bobsled, winter triathlon, ski-racing, cycling, bodyflight, skysurfing and gymnastics wear garments similar to catsuits, called unitards, which are specifically geared to the needs of the sport involved. Also similar in appearance are wetsuits and drysuits used by scuba divers, and the speedsuits used by competitive swimmers before the more extreme forms of the suit were banned. Also, in tennis Serena Williams would sometimes wear catsuits, two examples are the 2002 US Open and the 2018 French Open.

The name "catsuit" is attributed only since about 1955 or 1960.^[2][3] Originally, they were called bodysuits. The origin of the name is unknown; it may refer to a slinky, catlike aspect given the wearer by some versions.^[4] It may also relate to the association with antiheroine Catwoman whose costume from the 1950s onward is a modified catsuit.^[5]

The catsuit is often worn in movies, television, music videos, and computer games.

• In comics and their movie adaptations, catsuits are often worn by superheroes and supervillains, including the iconic Catwoman; other examples include Black Cat, Batgirl and Black Panther.
• Scarlett Johansson wears a catsuit portraying Natasha Romanoff-Black Widow in several films, beginning with Iron Man 2 (2010).^[6]
• The lead female characters of the Underworld film series and The Matrix wore catsuits.
• Female villains and heroines in spy films may wear catsuits, such as the Baroness and Scarlett in G.I. Joe: The Rise of Cobra.
• An iconic use of catsuits in popular media was on the British television show The Avengers, where Cathy Gale (Honor Blackman) and Emma Peel (Diana Rigg) wore tight leather catsuits; leather was chosen because it lit well in studio lighting and did not split during action scenes.
• Shirley Bassey wore a sleeveless chiffon catsuit for a gatefold album photograph, and in concert.^[7]
• Cher has worn catsuits in concert.^[8]
• In popular culture, catsuits have become the stereotypical costume of dominatrixes.
• Lara Croft, heroine of the Tomb Raider franchise, has worn catsuits in specific segments in Tomb Raider 3 and Tomb Raider: Chronicles.
• In the Star Trek: Enterprise TV series, the Vulcan commander T'Pol (portrayed by Jolene Blalock) wore a uniform sometimes described as a catsuit.^[9]
• The music video of Liberty X's 2002 smash hit "Just a Little" features two of its members, Jessica Taylor and Kelli Young, wearing tight black latex catsuits.^[10] On occasions where the group has performed the song live on television, both Taylor and Young wear their catsuits from the original music video.^[11][12] In 2013, when the group performed during the Big Reunion, both members wore a different design of their catsuits.^[13]