compartmentalization

The act or process of dividing a complex task or structure into smaller, often more manageable pieces.

(software) The act of dividing complex code into libraries with common functionality to help make the process of programming more manageable and reusable.

(counter-espionage) The act of dividing tasks involving confidential information so that no one person is capable of leaking enough to be incriminating. Alternatively, it can involve distributing information in such a way that no individual knows the full extent or purpose of the task they have been given, hence, if they are captured or monitored, the enemy would not be able to obtain useful information from any given person.