Tightlacing

An advertisement for corsets with waist sizes from 15 to 23 inches (38 to 58 cm)
A view of a woman in a corset and bloomers from the back with her hands on her hips. She has a very small waist.
A woman wearing a tight-laced corset, 1890. Note that Victorian photo editing techniques were likely used on this image, simulating a narrower waist.

Tightlacing (also called corset training) is the practice of wearing an increasingly tightly laced corset to achieve cosmetic modifications to the figure and posture or to experience the sensation of bodily restriction. The process originates in mid-19th century Europe and was highly controversial. At the peak of the prevalence of tightlacing, there was much public backlash both from medical doctors and dress reformers, and it was often ridiculed as vain by the general public. Due to a combination of evolving fashion trends, social change regarding the roles of women, and material shortages brought on by World War I and II, tightlacing, and corsets in general, fell out of favor entirely by the early 20th century.