"Nosferatu" means "a hideously ugly vampire," according to Dictionary.com. The precise origins of the word are unknown. It is likely Romanian in origin and may derive from the word "Necuratu," used to refer to the devil.
The word "Nosferatu" entered into common usage due to the success of Bram Stoker's 1897 novel "Dracula" and its 1922 film adaptation, "Nosferatu." Stoker claimed that he learned of the term from British author Emily Gerard, who first used the word in an 1885 article titled "Transylvanian Superstitions" and a travelogue titled "The Land Beyond the Forest." The word appears even earlier in an 1865 article by Wilhelm Schmidt discussing Transylvanian customs.