Young Brunette Girl With The Pink Corselette

The corselet was originally a piece of armor, covering the torso; the origin of the English word comes from cors, an Old French word meaning "bodice". The corselet as an item of women's clothing began to gain traction in 1914, as a substitute for wearing two separate pieces (a brassiere with either a girdle or a corset). The bust uplift cups were first introduced in 1933, but did not become common until 1943.
Merry widow
A corselet was released by Warner's in 1955, named after The Merry Widow, a 1905 operetta that has been adapted several times into feature-length films. This new design featured demi-cups and a shorter girdle than its predecessors. This type of lingerie is also known as a torsolette, and is used in bridal lingerie, much like the bustier.