A debutante is a young woman who is first introduced into society. In former times, these young ladies would be part of nobility, or the upper class. Originally, the term meant the young person was now old enough to be married. The purpose of the coming out was to display her to eligible bachelors and their families. The term comes from French, and can be translated as "beginner".
In those days, a young lady of quality could not meet anyone unless they were introduced to her. This introduction could happen at an event (such as a ball) which was part of the 'season'. In the United Kingdom there was a formal presentation of the debutants to the monarch at the Royal Court (abolished by the present Queen Elizabeth II in 1957). According to the peerage guide Debrett's, the traditional social season runs from April to August. The dress code for debutantes is traditionally a pure white ball gown and white evening gloves.