Zombie

A Zombie, also spelled zombi (PROSE: White Darkness) and in numbers referred to as the walking dead, (AUDIO: Mask of Tragedy), was a creature of the undead.

Although in some cases those referred to as “zombies” weren’t scientifically dead, they were typically always mindless beings.

Common attributes
The Fourth Doctor told Romana II that one could always identify a genuine zombie by the fact that their skin was cold to the touch. (TV: Destiny of the Daleks)

Horror movie zombies
In the early 21st century, zombies were often associated with movies. To Ianto Jones, the typical horror movie zombie wore ragged, stained clothes, had discoloured skin and appeared in various stages of decomposition. In the movies, in order to kill a zombie, it had to be shot in the head, destroying the brain. According to Rhys Williams, zombie outbreaks were always caused by "chemicals or radiation or something". (PROSE: Bay of the Dead)

Haitian voodoo
While not truly being "undead," it was possible (and often done by tribes in Haiti) to trick a human into believing they were one of the "living dead" using the drug tetrodotoxin. In correct doses, it could lower the consciousness of a person and take away their sensory nerves. The person would then be buried and dug up, making them think they had been brought back to life. They would subsequently be used as slaves. (PROSE: White Darkness)

Encounters with zombies
The living corpses animated by Sibelius Crow (and later by Carruthers Summerton based on Crow's work) were referred to as "zombies" by George Litefoot and Luke Betterman. (AUDIO: The Mourning After)

Rose Tyler called the Gelth, while possessing dead human bodies, zombies. (TV: The Unquiet Dead) To Sarah Jane Smith, she described people infected with the Empty Child virus as "gas mask zombies". (TV: School Reunion)

In 1939, the Seventh Doctor called the SS soldiers who had been conditioned by the War Lords, zombies. (PROSE: Timewyrm: Exodus)

In 2008, Sarah Jane Smith watched the people who had drunken Bubble Shock!, were under the control of the Bane Mother and were calling "Drink it". Sarah Jane thought they were spreading out like an army of zombies. (PROSE: Invasion of the Bane) A few time later Chrissie Jackson also compared these people to zombies. She told Maria Jackson that once Maria and Alan had moved in opposite Sarah Jane everyone had turned into zombies. (TV: Revenge of the Slitheen)

Behind the scenes

 * David A. McIntee, when writing White Darkness, took inspiration and facts from the non-fiction book The Serpent and the Rainbow, which detailed accounts of zombification that occurred in Haiti in the early 20th century. He advised staying away from the film version.
 * The humanoid antibodies created by the Exxilon City's "brain" to destroy the Third Doctor and Bellal in part four of Death to the Daleks were credited as "Zombies" in Radio Times.