A Gibson Girl...one who personified the ideal woman as drawn by Charles Dana Gibson from the 1890s to the early 1920s. The hourglass figures were achieved by use of constricting corsets which most women would wear when in public. When World War I came around, women wanted to wear practical clothes and not these constraining kinds, so the corsets disappeared, except for fancy ball gowns which remain an exception to this day.
By the 20's the fashions let women not only feel more natural in their attire, they sometimes went so far opposite the "Hourglass figures" as to flatten themselves in the flapper styles.
In the film industry, Marlene Dietrich became very popular in the 20s and 30s....and she was able to illustrate how feminine a woman could look in men's top hat and tails. She portrayed a cabaret singer thus as well as other leading ladies in many films...and was often considered a "vamp." She then was active in the 40s in inspiring the troops of the US and other countries against her native Germany. She had become an American citizen in 1939. She lived a long life, and made many films...dying at age 90.
Shown below is an ad using her pose for a British cigarette pack which had more photos enclosed. It's a good example of the slinky dress styles of 30's film stars.