A flapper was a certain type of woman in the United States in the 1920's. Flappers were known for their unconventional style and behavior.
In the United States in the 1920s, a certain kind of woman emerged: the flapper. Flappers had their own hairstyles and ways of dressing, especially bobbed hair and short skirts. They liked to listen to jazz and generally embraced freedom from social conventions. None of this was considered "ladylike" at the time: it was new and shocking. Flappers were a sign of changing times and more freedom for women to express themselves. There's no doubt the flappers had a lot of style.