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cerebellum cer·e·bel·lum (sěr'ə-běl'əm)
n. pl. cer·e·bel·lums or cer·e·bel·la (-běl'ə)
The trilobed structure of the brain, lying posterior to the pons and medulla oblongata and inferior to the occipital lobes of the cerebral hemispheres, responsible for the regulation and coordination of complex voluntary muscular movement and the maintenance of posture and balance.
Plural cerebellums or cerebella
The part of the vertebrate brain that is located below the cerebrum at the rear of the skull and that coordinates balance and muscle activity. In mammals, the cerebellum is made up of two connecting hemispheres that consist of a core of white matter surrounded by gray matter.
The part of the brain that helps control muscle coordination.