Screen Sirens were a type of glamorous female movie star popular in the 1920s and 1930s. They were often characterized by their alluring beauty, sultry voices, and seductive mannerisms. The term 'Screen Siren' was derived from the VAMP (4 letters) acronym, which stands for 'Vitality, Allure, Magnetism, and Personality'. These stars were known for their ability to captivate audiences with their charm and charisma.