A chaperone (or occasionally chaperon) is an adult who accompanies or supervises one or more young, unmarried men or women during social occasions, usually with the specific intent of preventing inappropriate social or sexual interactions or illegal behavior (e.g., underage drinking or illegal drug use). The chaperone is typically accountable to a third party, usually the parents of one of the accompanied young people.
The word derives figuratively from the French word chaperon (originally from the Late Latin cappa, meaning "cape") which referred to a hood that was worn by men and women generally. A chaperone was part of the costume of the Knights of the Garter when they were in full dress and, probably, since the Knights were court attendants, the word chaperon changed to mean escort. An alternate explanation comes from the sport of falconry, where the word meant the hood placed over the head of a bird of prey to stop its desire to fly.
Traditionally, a chaperone was an older married or widowed woman accompanying a young woman when men would be present. Her presence was a guarantee of the virtue of the young woman in question. The English derivate "duenna" seems to come from dueña, the Spanish old form for doña, or "mistress." Chaperones for young men were not commonly employed in Western society until the latter half of the 20th century.
Chaperones may be resisted and resented by the young people being supervised. The practice of one-on-one chaperones for social occasions has largely fallen out of use in Western society, though the term is often applied to parents and teachers who supervise school dances and field trips.
The concept of a chaperone is also used in variation. For example, a chaperone might be an expert in a given activity who takes a group and accompanies them during outside activities to provide physical support, advice and emergency attention if necessary. Sometimes the term is applied to people who are essentially tour guides (as were the bear-leaders of the Grand Tour in previous times). In addition, the term is used as a verb similar to "guide" (e.g., "I'll chaperone you around the city and show you all the best places.")
In drama, probably the best known example of a plot revolving around the need for, and lack of, a chaperone is Brandon Thomas's farce Charley's Aunt (1892).
The chaperone is spoofed in the 2006 musical The Drowsy Chaperone.
Cosmo Kramer acts as a chaperone for Jerry Seinfeld and Miss Rhode Island on an episode of Seinfeld.