cerebellum

https://doi.org/10.1351/goldbook.11669
Lower part of the brain that is beneath the posterior portion of the cerebrum, regulating the unconscious coordination of movement.
Source:
PAC, 2015, 87, 841. (IUPAC Glossary of terms used in neurotoxicology (IUPAC Recommendations 2015)) on page 856 [Terms] [Paper]