Decapitation is the process of cutting someone's head off of their neck. Decapitation is another common form of slaying a vampire.
Some vampires, such as the German Nachzeher, can only be slain through decapitation (in this case, after placing a coin in its mouth)
Count Dracula was also decapitated in the book, and Lucy Westenra is also sometimes portrayed as being decapitated (although in the book, she was traditionally staked through the heart).
Some vampires, such as Alucard from Hellsing, are shown to be powerful enough to survive this, however, it is rare.