I am looking for an umbrella term for general "parts of the brain", esp. for (somehow arbitrary) "subsets of neurons".
For the tree of life there is an umbrella term for all kinds of taxonomic groups all down the tree. They are called taxa.
Domains, kingdoms, phylums all down to families, genus, and species are taxa:
In brain sciences there seems to be no such umbrella term which is generally agreed upon.
Which term would best include all of the following?
brain hemispheres
coarse brain subdivisions (cerebellum, cerebrum, ...)
cerebral lobes (frontal, parietal, ...)
the thalamus („a large mass of gray matter“)
nuclei (thalamic, ...)
Brodman areas
cortical layers
cortical columns
the limbic system
regions of interest (in fMRI)
All of these immediate suggestions don't fit perfectly:
(brain) region
(brain) division
(brain) area
(brain) volume
(neural) group
(functional) system