what is the term mentioned last?
It is a major feature of the hindbrain of all vertebrates
Cerebellum
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. 
which part of the brain contains the most neurons The cells of the brain briefly describe the human brain? It is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. It consists of the cerebrum, the brainstem and the cerebellum
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Cerebellum [SEP] Introduction
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language as well as emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity.