Final answer:
The term for a user or process that attempts to access an object in a secure system is called the subject.
Step-by-step explanation:
A user or a process functioning on behalf of the user that attempts to access an object is known as the subject. Within security models, the subject is an active component, typically a user or a system entity that requests access to a resource or data, which is referred to as the object. Access control mechanisms within systems often involve a reference monitor, which is a concept or often an implementation of a part of the system responsible for enforcing access controls, ensuring that subjects are only able to access objects for which they are granted permissions.