An evening gown is a long flowing women's dress

Dress

A dress is a garment consisting of a skirt with an attached bodice or with a matching bodice giving the effect of a one-piece garment.Dress may also refer to:*Clothing in general*Costume, fancy 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

Chiffon (fabric)

Chiffon, , from the French word for a cloth or rag, is a lightweight, balanced plain-woven sheer fabric woven of alternate S- and Z-twist crepe yarns. The twist in the crepe yarns puckers the fabric slightly in both directions after weaving, giving it some stretch and a slightly rough...

, velvet

Velvet

Velvet is a type of woven tufted fabric in which the cut threads are evenly distributed,with a short dense pile, giving it a distinctive feel.The word 'velvety' is used as an adjective to mean -"smooth like velvet".-Composition:...

, satin

Satin

Satin is a weave that typically has a glossy surface and a dull back. It is a warp-dominated weaving technique that forms a minimum number of interlacings in a fabric. If a fabric is formed with a satin weave using filament fibres such as silk, nylon, or polyester, the corresponding fabric is...

, or silk

Silk

Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...

. Although the terms are used interchangeably, 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...

s and evening gowns differ in that a ball gown will always have a full, flared skirt and a strapless bodice; in contrast, an evening gown can be any silhouette—sheath

Sheath dress

In fashion, a sheath dress is a type of dress designed to tightly fit the body. It is often made of a very light and thin material like cotton or silk, and rarely contains any flourishes. Unlike the shorter cocktail dress and the longer ballroom dress, a sheath dress typically falls around the...

, mermaid

Mermaid

A mermaid is a mythological aquatic creature with a female human head, arms, and torso and the tail of a fish. A male version of a mermaid is known as a "merman" and in general both males and females are known as "merfolk"...

, A-line

A-line

An A-line skirt is a skirt that is fitted at the hips and gradually widens towards the hem, giving the impression of the shape of a capital letter A. The term is also used to describe dresses and coats with a similar shape.-History:...

 or trumpet

Trumpet

The trumpet is the musical instrument with the highest register in the brass family. Trumpets are among the oldest musical instruments, dating back to at least 1500 BCE. They are played by blowing air through closed lips, producing a "buzzing" sound which starts a standing wave vibration in the air...

 shaped—and may have straps, halters

Halterneck

Halterneck is a style of strap which holds up women's clothing which features a single strap or material which runs from the front of the garment around the back of the wearer's neck, and which enables most of the wearer's back to be uncovered...

 or even sleeves.

It corresponds to men's semi-formal wear for 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...

 events.
In the Middle Ages, formal dress for women had yet to be developed.