Lifeform

A lifeform was a generic term for a living being.

A number of silicon-based lifeforms were encountered by the Doctor, including the Kastrians (TV: The Hand of Fear), Ogri (TV: The Stones of Blood) and Plutonians (PROSE: GodEngine).

In the 29th century, Taren Capel tried to start a robot revolution, as he believed robots to be a superior lifeform and wanted to liberate them. (TV: The Robots of Death)

CAIN was an artificial lifeform on the Myriad, with a fungoid brain. (AUDIO: The Pyralis Effect)

Strange icarons had no harmful effects on organic lifeforms, but interfered with starship jump engines. (PROSE: GodEngine) Conversely, normal icarons "preferred" to be in hyperspace and caused paranoia and psychotic behaviour in carbon-based lifeforms. (PROSE: Original Sin)

Gabrielideans were a liquid-based lifeform. One of their soldiers fighting for the Time Lords in their War against the enemy was captured and turned into an idea-based lifeform known as the Shift. (PROSE: Alien Bodies)

When the Tenth Doctor and Donna Noble visited the Library, its computers confirmed they were the only humanoid life present, but then told them there were over "a million million lifeforms" in the Library. (TV: Silence in the Library)