A vampire was a creature from Earth mythology, 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 was often invoked whenever lifeforms who instinctively and necessarily feed on others are encountered.
In 2372, a 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")