Topic summary
décolletage

Extracted from the Wikipedia article Cleavage (breasts).
Décolletage started becoming popular in the Christian West as it came out of the Early Middle Ages and enjoyed significant prevalence during mid-Tang-era China, Elizabethan-era England, and France over many centuries, particularly after the French Revolution. But in Victorian-era England and during the flapper period of Western fashion, it was suppressed. Cleavage came vigorously back into Western fashion in the 1950s, particularly through Hollywood celebrities and lingerie brands. The consequent fascination with cleavage was most prominent in the U.S., and countries heavily influenced by the U.S. With the advent of push-up and underwired bras that replaced the corsets of the past, the cleavage fascination was propelled by these lingerie manufacturers. By the early 2020s, dramatization of cleavage started to lose popularity along with the big lingerie brands. At the same time cleavage was sometimes replaced with other types of presentation of partially clothed breasts, like "sideboob" and "underboob".