Wiktionary
n. 1 division into compartments 2 (context military English) Establishment and management of an organization so that information about the personnel, internal organization, or activities of one component is made available to any other component only to the extent required for the performance of assigned duties. 3 (context military English) Effects of relief and drainage upon avenues of approach so as to produce areas bounded on at least two sides by terrain features such as woods, ridges, or ravines that limit observation or observed fire into the area from points outside the area. (JP 3-05.1)
Usage examples of "compartmentation".
Stored supplies, massive in themselves, could be retained in convenient order by compartmentation of eggshell-thin transparent plastic.
The compartmentation creaked, and I knew we were well into New Providence Channel, where we would take the sweep of the weather.
Even Wyoh admitted that organization without compartmentation could not work after she learned how rotten with spies old underground had been.