1 a corpse supposed, in European folklore, to leave its grave at night to drink the blood of the living by biting their necks with long pointed canine teeth.
Well, that's really quite hard to say because most of the sub-cultures that embrace the vampiric lifestyle do not, in fact, drink blood, but do believe that they find sustenance in some form or another that isn't typical for the human race. The ones that I know exist (i.e there have been confirmed encounters/research/interviews with followers) include psychic vampires, who seek nourishment from others by 'sucking' on their energy or 'chi'; Spirit-influenced vampires who seem to gain elements of vampire like strength (or believe they are in fact in possession of, at any rate) from some pact with a spirit or demon; viral vampires who are the ones who actually do drink blood and/or believe themselves to be carrying the vampire 'gene'. These so called vampires actually tend to have people who they call 'donors', that give them blood at regular intervals. They've got a really, really large online community.