A babydoll is a short nightgown or negligee intended as nightwear for young ladies. The garment is often trimmed with lace, ruffles, appliques, Marabou fur, bows and ribbons, optionally with spaghetti straps. Sometimes it is made of sheer or translucent fabric like nylon or chiffon or silk. The garments hemline is usually about six inches above the knee like a Minidress and may have a scoopneck. They are usually considered provocative.

It is said the name was popularized by the 1956 movie Baby Doll starring Carroll Baker in the title role, which essentially marked the beginning of the enduring popularity of the style for adults. At the same time, new synthetic fabrics and boutique retailing made the form both affordable and easy to purchase.

Short daywear dresses of a similar style are sometimes called babydoll dresses; the name is sometimes two words, baby doll, and sometimes hyphenated, baby-doll. Some styles are similar to what is worn by dolls in the form of infants, and by some infants; the gown is short enough that diapers are easily changed. Thus, it is a common garment for those who indulge in sexualized play-acting around ideas of infantilism. However, there may be an alternative origin for the style, if we consider the lineage of lace-trimmed shortie bed-jackets and bed-capes of the 1930s and 1940s.