An accumulation of bodies of neurons is called?

The accumulation of bodies of neurons is called nerve nodes, or ganglia. A ganglion is a group of neuronal cell bodies at the periphery. Ganglia are the nodal masses of neuronal cell bodies (ganglion cells) along with their supporting neuroglia (capsular cells). There are two types of ganglia:

sensory ganglia – the cell bodies of sensory neurons. The most common type of sensory ganglion is the dorsal (posterior) ganglion.
autonomic ganglia – the cellular bodies of the efferent neurons of the autonomic nervous system.