
A 
femme fatale character in movies or books. The character is a woman who, while not necessarily attractive, has a certain allure (usually this striking, exotic, overtly sexy glamour), and is usually a heartless, man-eating seductress. The term is short for 
vampire, another term for a femme fatale.
In 
drama, the vamp is the sexual counterpoint for the naive, wholesome 
ingenue character. The sultry lower voice of the 
mezzo-soprano is usually reserved for the vamp character in 
musicals or 
opera. 
The ultimate silent screen vamp was Theda Bara. This is a spin off from Theda who is the greatest all-time vamp.