vampire

noun

1. A mythological creature (usually humanoid and undead) said to feed on the blood or life energy of the living.

   “Bram Stoker's novel Dracula built on centuries-old stories of vampires and also encouraged new growth of the mythology.”

   “The universal belief is, that a person sucked by a vampyre becomes a vampyre himself, and sucks in his turn.”

   “From my laboratory in the Castle east To the master bedroom, where the vampires feast The ghouls all came from their humble abodes To get a jolt from my electrodes They did the Mash They did the Monster Mash.”

   “I'm a vampire, baby, sucking blood from the earth / Well, I'm a vampire, baby, sell you twenty barrels worth”

2. (colloquial, humorous, usually)A person with habits traditionally ascribed to (literal) vampires, such as heliophobia, being a night owl, having pale skin, and so on.

   “Near-synonyms: heliophobe, goth”

   “Somehow I doubt that Kelly will want to go surfing with us — she's such a vampire that she might recoil from the sun, lol!”

3. (colloquial)A person with the medical condition porphyria cutanea tarda, colloquially known as vampirism, with effects such as photosensitivity and brownish-red stained teeth.
4. A blood-sucking bat; vampire bat (Desmodus rotundus)
5. (derogatory, figuratively)A person who drains one's time, energy, money, etc.

   “emotional vampire”

   “You have to be careful what you tell her, because she's such a vampire for drama.”

6. (dated)A vamp: a seductive woman who exploits men.

   “"What followed this decision was exactly what we had expected: Mr. Fox, realizing that the public was tiring of Theda Bara in vampire roles, announced that he would star her in a production of Romeo and Juliet," she illustrated.”

7. (US, slang)A medical technician who works with patients' blood; especially, a phlebotomist.

   “Only one technician in the hospital lab, in all we have encountered, uses it. […] Eric makes no complaints other than those directed at the vampires. Brenda and I do.”

   “"I draw blood from patients, and then I take it back to the lab and analyze it. Sometimes, the vampires do all the sticks, that is to say the lab assistants do all the blood collections." He grinned. "We have our own language at the lab."”

8. (US, jargon)Synonym of anti-ship missile (ASM), particularly an incoming hostile one.

   “Vampire. Vampire. Vampire. Battle stations.”

verb

1. (figuratively, transitive)To drain of energy or resources.