Head
The head was where the brain was located.
The Ninth Doctor used the head of the Auton duplicate of Mickey Smith to trace the signal of the Nestene Consciousness. (TV: Rose)
Before the Ninth Doctor regenerated, he speculated his next incarnation could have two heads or none at all. (TV: The Parting of the Ways)
Among the artefacts in the Vault were the heads of a Mondasian Cyberman, an Earth reptile and a scarecrow. (TV: Dalek)
On Skaro, the Terrorkons had two heads. (COMIC: Terrorkon Harvest)
The Aplans were humanoid lifeforms with two heads. The heads apparently had their own separate intelligences and personalities. (TV: The Time of Angels)
Amy Pond was afraid that travelling in the TARDIS while pregnant would have some sort of effect on the baby, suggesting it could have three heads "or, like, a timehead or something." (TV: Day of the Moon)
The natural design of the 456 consisted of three "heads", connected to one body via three long necks, possibly a conjoined triplet species. It resembled a large, plucked, three-headed swan. (TV: Children of Earth: Day Four)
Corpse Gipe resembled a vulture with three heads. (PROSE: Time Lapse)
The natives of the planet Thursday shrunk the heads of their enemies and displayed them as a warning. (COMIC: The Trick)
The people of Harmony kept the living disembodied heads of visitors who were scientifically minded in glass cases to make use of their intelligence. The Second Doctor discovered the room in which the heads were kept during his visit to Harmony. (PROSE: Planet of Bones)