Vampire: An animated corpse that drinks blood in order to sustain itself.
OR
A human, creature, spirit or other entity that drains anything-- blood, energy, etc.-- from humans or animals to sustain its way of life.

Vampirism: The act of taking fluid or energy from another person.

Vampir: Hungarian name for Vampire.

These are the more classical Gothic vampires, and probably the most human of the supernatural beings. Vampyr follow sex-and-death vampirism, they seduce their victims before killing them.

Vampyr are formed by ingesting the blood of another vampyr, this brings on a progressive degeneration of the vampyr-to-be. The degeneration appears to be a virulent disease, with affects similar to severe anemia. After a relatively short period, the 'victim' will appear to die and return to life on the next nightfall. Thus, the new vampyr is born.

Generally, the requirement for human blood turns the new vampyr to a life that most people describe as evil. Lone vampyr tend to end up being killed within a month or so. There are a couple of groups of vampyr who can generally keep their members alive for a longer time: the Lilim (Children of Lilith) and the Children of Cain.

Vampyr can be killed by fire, exposure to sunlight or decapitation. A stake through the heart immobilises them, but does not kill them. Starving of blood will reduce them to a corpse, but this corpse can reanimate if supplied with blood.

Vampiress: A female vampire.

Vampire Demi-god: Entities who are neither demon nor spirit. Demi-gods, or lesser gods, are often god hybrids or low ranking gods who traditionally do not interact with the mortal population, unless it is in legend. A vampire demi-god is a figure in mythology which acts in a manner consistent with folkloric vampires. These lesser gods are, I believe, the beginnings of the vampire, who eventually de-evolved from a god- splitting then, perhaps, into the other related forms of spirits and demons- to a very tangible, and formally mortal, corpse.

Vampire Society: Most solitary vampires, at least the supernatural ones, will end up dead. Since this happens, vampires tend to form groups for support. There are various small groups in every town, but there are two important groups: The Children of Cain and The Lilim.

Varacolaci: Romanian. This vampire that ranks among the most powerfull of all the undead, as possesses the ability to cause both lunar and solar eclipses. The Varacolaci may appear as pale humans with dry skin, and they can travel on an astral thread, the midnight spinning, travelling as far as need as long as the thread remains unbroken.

Vetala: Hindu vampires whose hands and feet are turned backward which reanimate the dead.

Volkodlak: Slovenian. The Volkolak is linked in some ways to various werewolf legends.

Vourdalak: Russian. In Russian folklore, this Vampire is considered to be a beautiful but evil woman.

Vrykolakas: This Greek name is interchangeable with Lampir(Bosnian), Vurvulak(Albanian), Upirina(Serbo-Croatian), and Vukodlak(Croatian). It is an evil being amongst the Southern Slavs that attacked people at night. It is said that there was one for every Slavic clan.

Vrykolatios: A vampire species found on the island of Santorini. They are described as fiends which banquet on the living.

Vukodlak: A Slavic Vampire-Werewolf which rises from its grave to drink blood and have sex with its former spouse.

Vurvulak: See Vrykolakas.

Vyrkolakas: Greek name for Vampire.