A vampire is the manifestation of an Earth legend of a creature who had previously been a living Human, and had returned from death to feast on the blood of others. As with many legends, parts of this lore described real traits of actual creatures, and the term is often invoked whenever lifeforms who instinctively and necessarily feed on others are encountered.
In 1953, a memo Herbert Rossoff had above his desk from Douglas Pabst read "No one would believe that a cheerleader could kill vampires". (DS9: "Far Beyond the Stars")
Joseph Sisko compared the two security officers, who performed blood screenings, to vampires and told his son to order them to sit down and take a menu or leave his restaurant. (DS9: "Homefront")
In 2372, an unnamed Starfleet security chief on Earth likened a security officer to a vampire, as she was to perform a blood screening on him. She reminded him that vampires only come out at night. (DS9: "Paradise Lost")