closed loop

Noun

1. A path whose initial point is equal to its terminal point.
2. Alternative form of closed curve.
3. A feedback loop, especially when found in:

   1. (cybernetics) A closed-loop transfer function.

   2. (systems theory) An electronic feedback loop.

   3. (systems theory) A PID controller.

4. A closed ecological system.
5. Closed-loop communication.
6. The process of pulling water from one area of a reef aquarium and pumping it immediately elsewhere in the tank to create higher flow and minimize dead spots.
7. An economy in which materials are consistently reused rather than discharged as waste.
8. Clipping of closed time loop.
9. Alternative form of knot loop.