demimonde

noun

1. (especially during the last half of the 19th century) a class of women who have lost their standing in respectable society because of indiscreet behavior or sexual promiscuity.
2. a demimondaine.
3. prostitutes or courtesans in general.
4. a group whose activities are ethically or legally questionable: a demimonde of investigative journalists writing for the sensationalist tabloids.
5. a group characterized by lack of success or status: the literary demimonde.

noun

1. (esp in the 19th century) those women considered to be outside respectable society, esp on account of sexual promiscuity
2. any social group considered to be not wholly respectable