archicerebellum
/ˌɑːkɪsɛrɪˈbɛləm/Anatomy
noun
The phylogenetically oldest portion of the cerebellum, a small region usually held to comprise the nodulus and the flocculi, receiving nerve fibres especially from the vestibule of the inner ear.
Origin
1930s; earliest use found in Olof Larsell (1886–1964). From archi- + cerebellum.