The term "costume de rigueur"^[p] (from French language

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

) refers to a strict dresscode for the attire worn at a special event or in a particular venue. It is commonly used in invitations to a bal masque for the Mardi Gras in Mobile

Mardi Gras in Mobile

Mardi Gras in Mobile, Alabama[pronounce] is the oldest annual Carnival celebration in America, having begun in 1703,over 15 years before New Orleans was founded ....

 (Alabama

Alabama

Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

) or New Orleans Mardi Gras

New Orleans Mardi Gras

Mardi Gras in New Orleans, Louisiana, is a Carnival celebration well-known throughout the world.The New Orleans Carnival season, with roots in preparing for the start of the Christian season of Lent, starts after Twelfth Night, on Epiphany . It is a season of parades, balls , and king cake parties...

 (Louisiana

Louisiana

Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...

) in the U.S. However, the term is also used to describe any rigorous style of attire as worn. As a phrase adapted from French, the term "costume de rigueur" is not italicized in typical usage, although still used in French language.

For Mardi Gras balls

For over 100 years, at a formal bal masque during Mardi Gras

Mardi Gras

The terms "Mardi Gras" , "Mardi Gras season", and "Carnival season", in English, refer to events of the Carnival celebrations, beginning on or after Epiphany and culminating on the day before Ash Wednesday...

 celebrations in the U.S., the stipulation of "costume de rigueur" means that men are required to wear white tie and tails (with white bow tie

Bow tie

The bow tie is a type of men's necktie. It consists of a ribbon of fabric tied around the collar in a symmetrical manner such that the two opposite ends form loops. Ready-tied bow ties are available, in which the distinctive bow is sewn into shape and the band around the neck incorporates a clip....

), or women should wear a full-length evening gown

Evening gown

An evening gown is a long flowing women's dress usually worn to a formal affair. It ranges from tea and ballerina to full-length. Evening gowns are often made of a luxury fabric such as chiffon, velvet, satin, or silk...

.

Related terms

The phrase "de rigueur" refers to a rigorous style or manner. Some related terms are:

• "de facto
  De facto
  De facto is a Latin expression that means "concerning fact." In law, it often means "in practice but not necessarily ordained by law" or "in practice or actuality, but not officially established." It is commonly used in contrast to de jure when referring to matters of law, governance, or...
  
  " - meaning in the manner used in actual fact
• "de jure
  De jure
  De jure is an expression that means "concerning law", as contrasted with de facto, which means "concerning fact".De jure = 'Legally', De facto = 'In fact'....
  
  " - meaning in the manner officially decided or adjudicated.

All terms have been used for over 100 years.

See also

Joe Cain Day Ball gown Ball gown A ball gown is worn for ballroom dancing and only the most formal social occasions according to rules of etiquette. It is traditionally a full-skirted gown reaching at least to the ankles, made of luxurious fabric, delicately and exotically trimmed. Most versions are cut off the shoulder with... Black tie Black tie Black tie is a dress code for evening events and social functions. For a man, the main component is a usually black jacket, known as a dinner jacket or tuxedo...

cocktail dress Cocktail dress A cocktail dress or cocktail gown is a woman's dress worn at cocktail parties, and semi-formal, or "black tie" occasions.The length of cocktail dresses varies depending on fashion and local custom. The length ranges from just above the knee to touching the ankle... krewe Krewe A krewe is an organization that puts on a parade and or a ball for the Carnival season. The term is best known for its association with New Orleans Mardi Gras, but is also used in other Carnival celebrations around the Gulf of Mexico, such as the Gasparilla Pirate Festival in Tampa, Florida, and...

mystic society Mystic society A mystic society is a Carnival social organization, similar to a krewe in New Orleans, that presents parades and/or balls for the enjoyment of its members, guests, and the public. The term came to be used in this context in Mobile, Alabama. Mystic society membership is secret. The societies have... Order of Myths Order of Myths The Order of Myths, founded in 1867,is the oldest remaining mystic society to celebrate Mardi Gras in Mobile, Alabama. The Order of Myths chose, as its symbolic emblem, Folly chasing Death around a broken column of life, imagery that was considered, following the American Civil War, as a symbol of...