(mathematics, physics) A system which is time-dependent.

dynamical system

(physics, chemistry, engineering) A physical system whose interaction with its environment is limited to particular types of transfer, so that certain quantities are conserved within the system.

(physics) A system that does not interact with its surroundings. Depending on context this may mean that its total energy and/or momentum stay constant. In thermodynamics, isolated is usually used to indicate that the system's energy does not change. In mechanics it is used to indicate that the system's momentum does not change.

(computing) A computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints.

plural of solar system

plural of sub-system

A computer system that uses techniques derived from artificial intelligence, particularly one in which such techniques are central to the operation or design of the system.

plural of intelligent system

(astronomy) A heliocentric model of the solar system, proposed in the 16th century by the eponymous astronomer.