Final answer:
The term defined by NIMS as the act of directing or controlling is 'command', which is based on explicit legal authority given to certain officials or agencies.
Step-by-step explanation:
The term that NIMS defines as the act of directing, ordering, or controlling by virtue of explicit statutory, regulatory, or delegated authority is command. This authority is granted by law to an executive department or agency, or to the head thereof, and includes the functions of the Director of the office of management and budget within the executive office of the President.
The concept of command plays a crucial role in emergency management and response protocols, where clear lines of authority and control are essential for effective operation.
For example, during a large-scale disaster, the Incident Commander has command authority, which allows them to make critical decisions about resource allocation, emergency operations, and interagency coordination, based on their explicit authority defined within NIMS.