Final answer:
An open system is one that loses energy to objects that are not part of the system. It differs from an isolated system, which does not allow for the transfer of energy or matter. The behavior of these systems is governed by the laws of thermodynamics.
Step-by-step explanation:
The term used to describe a system that loses energy to objects that are not part of the system is an open system. An open system can exchange both energy and matter with its surroundings. This is in contrast to an isolated system, which allows neither energy nor matter to be transferred in or out.
The laws of thermodynamics, including the concept of entropy, govern the behavior of these systems. In all energy transfers, some usable energy is lost to the surroundings, usually in the form of heat, increasing the entropy of the universe. Biological organisms, for example, are open systems that exchange energy with their environment.