The Vampire language is a tongue used by intelligent vampires; namely alps, mulas, bruxae, higher vampires and in all likelihood also katakans and nosferats.
A song in this language, described as silent, shrill and spilling sickening, overwhelming horror into one's veins, was sung by Vereena to take control of Nivellen's mind.[1]
After Geralt's company left the Lyrian Army and stole from its supplies in order to survive a long journey south, Regis received a mule which he named Draakul. When asked by his human friends what it means he explained it had an amusing significance in the culture and speech of vampires but was "an untranslatable pun".[2]