A hoop skirt or hoopskirt is a women's undergarment

Undergarment

Undergarments or underwear are clothes worn under other clothes, often next to the skin. They keep outer garments from being soiled by bodily secretions and discharges, shape the body, and provide support for parts of it. In cold weather, long underwear is sometimes worn to provide additional...

 worn in various periods to hold the skirt

Skirt

A skirt is a tube- or cone-shaped garment that hangs from the waist and covers all or part of the legs.In the western world, skirts are usually considered women's clothing. However, there are exceptions...

 extended into a fashionable shape.

Hoop skirts typically consist of a fabric petticoat

Petticoat

A petticoat or underskirt is an article of clothing for women; specifically an undergarment to be worn under a skirt or a dress. The petticoat is a separate garment hanging from the waist ....

 with casing

Casing

Casing may refer to:* Cartridge , shell enclosing the explosive propellant in ammunition* Casing , metal tube used during the drilling of a well* Casing , decorative molding surrounding door or window openings...

s to hold a stiffening material, variously rope

Rope

A rope is a length of fibres, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength...

, osiers

Willow

Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...

, whalebone, steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

, or nylon

Nylon

Nylon is a generic designation for a family of synthetic polymers known generically as polyamides, first produced on February 28, 1935, by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station...

.

Hoop skirts are called by various names in different periods:

• Farthingale
  Farthingale
  Farthingale is a term applied to any of several structures used under Western European women's clothing in the late 15th and 16th centuries to support the skirts into the desired shape. It originated in Spain.- Spanish farthingale :...
  
   (Spanish verdugado} (16th century)
• Pannier
  Pannier (clothing)
  Panniers or side hoops are women's undergarments worn in the 18th century to extend the width of the skirts at the side while leaving the front and back relatively flat...
  
  s or "side hoops" (18th century)
• Crinoline
  Crinoline
  Crinoline was originally a stiff fabric with a weft of horse-hair and a warp of cotton or linen thread. The fabric first appeared around 1830, but by 1850 the word had come to mean a stiffened petticoat or rigid skirt-shaped structure of steel designed to support the skirts of a woman’s dress into...
  
   (mid-19th century)
• Bustle
  Bustle
  A bustle is a type of framework used to expand the fullness or support the drapery of the back of a woman's dress, occurring predominantly in the mid-to-late 19th century. Bustles were worn under the skirt in the back, just below the waist, to keep the skirt from dragging. Heavy fabric tended to...
  
   (later 19th century)

Lightweight hoop skirts, usually with nylon hoops, are worn today under very full-skirted wedding gowns. They can sometimes be seen in the gothic fashion

Gothic fashion

Gothic fashion is a clothing style worn by members of the Goth subculture; a dark, sometimes morbid, eroticized fashion and style of dress. Typical Gothic fashion includes dyed black hair, black lips and black clothes. Both male and female goths wear dark eyeliner and dark fingernails. Styles are...

 scene. Reproduction hoop skirts are an essential part of living history

Living history

Living history is an activity that incorporates historical tools, activities and dress into an interactive presentation that seeks to give observers and participants a sense of stepping back in time. Although it does not necessarily seek to reenact a specific event in history, living history is...

 costuming, including American Civil War reenactment

American Civil War reenactment

American Civil War reenactment is an effort to recreate the appearance of a particular battle or other event associated with the American Civil War by hobbyists known as Civil War reenactors or Civil War recreationists...

.