A cerebellar neoplasm that occurs in an adult. The disease is adult cerebellar neoplasm (Monarch Disease Ontology identifier MONDO_0003260). Also known as: adult cerebellar neoplasms, adult cerebellar tumor, adult cerebellar tumors, adult cerebellar tumour, adult cerebellar tumours, cerebellar neoplasm of adults, neoplasm of adult cerebellum, neoplasm of the adult cerebellum.