Vintage Fashion Glossary: Where the Terms Come From

Age words

Antique: Used for items 100 years old or more (Wikipedia, Vintage clothing).
Vintage: Garments made roughly 30 to 100 years ago that clearly reflect the styles of their era, by the definition Wikipedia gives. Sellers use the word more loosely, so check what a listing means by it.
Retro: Short for retrospective: usually new clothing that imitates an earlier era. Retro is a style, not an age.
Deadstock: Merchandise withdrawn from sale and warehoused without ever being sold to a customer. When old deadstock comes back on the market it is sold as vintage, often with original tags.
Vintage-inspired / vintage reproduction: Modern, usually mass-produced interpretations of older designs, often offered in a wider size range.

Negligee: From the French négligé, literally “neglected”; also called déshabillé, “undressed”. A sheer, usually long dressing gown for the bedroom. It began in 18th-century France, imitated satin evening dresses in the 1920s, and generally grew shorter between the 1940s and 1970s.
Babydoll: A short nightgown style; Wikipedia cites the 1970s babydoll as an example of the negligee's shortening hemline.
Combinations: A one-piece undergarment joining top and drawers. Men's combinations were patented in 1862; women's versions combining a chemise and drawers appeared in 1877.
Camiknickers (chemi-knickers, envelope chemise): A one-piece camisole-and-knickers garment that appeared in the 1910s.
Step-ins: One of several 1920s names for the camiknicker style, alongside cami-combinations and cami-bockers.
Teddy: A one-piece undergarment covering torso and crotch. The style is said to be named after the German-American clothing manufacturer Theodore Bear; “teddy” became the common term in the 1970s, and a spandex revival followed in the 1980s–1990s.
Bias cut: Cutting fabric diagonally to the grain (45° is “true bias”) so it stretches and drapes. Championed by Madeleine Vionnet from the 1920s, it defined early-1930s evening wear and slips.

ILGWU: International Ladies' Garment Workers' Union, founded June 3, 1900, which adopted a label the same day. Its label changed design in 1959, 1963 and 1974 (red, white and blue, with “Made in the U.S.A.”), and the union merged into UNITE in 1995. See reading the label.
Blue Eagle: The National Recovery Act label of 1933; the Vintage Fashion Guild dates its use to 1933–1935.
AFL-CIO: Union labels reading “AFL-CIO” instead of “AFL” date from 1955 or later, the year of the merger.
RN: Registered Identification Number, issued by the FTC to US businesses covered by the Textile, Wool and Fur Acts; it can replace the company name on a label.
WPL: An older number the FTC issued under the Wool Products Labeling Act. No longer issued, but still valid and used like an RN.
Care label: Permanent washing or cleaning instructions, required under the FTC's Care Labeling Rule of 1971; symbols in place of words were allowed from 1997.
Woolmark: The wool symbol, first used in 1964 (Vintage Fashion Guild).

Rayon: Its manufacturing process was developed in France in 1855; the name “rayon” dates from 1924. Common in lingerie and dresses until the 1950s.
Nylon: Developed by DuPont in 1938 and sold to consumers as stockings from May 1940; used in other clothing after WWII.
Dacron: A polyester yarn, used in clothing from 1953.
Spandex (elastane): Developed by DuPont in 1958 and used in lingerie from 1960.
Qiana: A silky nylon, commercially available from 1968 — a strong 1970s clue.

Lockstitch / chain stitch: Chain stitch came first; lockstitch seams are rare before 1870.
Serger (overlock): A machine for overlocking seam edges; first patented by Merrow in 1889 and used for seam finishing since the 1920s.
Side zipper: A zipper in the left side seam of a dress, typical from the late 1930s to the 1960s.
Coil zipper: A plastic coil zipper, invented in 1940 and common only from the early 1960s. The word “zipper” itself came from B.F. Goodrich's rubber boots in 1923.

Misses: Even-numbered sizes for women of about average height.
Juniors: Odd-numbered sizes (1–15) cut for a shorter, straighter figure with a higher bust.
Women's: Even sizes from 18 up for larger women of average height. Size numbers have grown over time — see vintage vs modern sizing.