closed loop

¹

[ klohzd loop ]

noun

1. Computers, Electronics. the complete path followed by a signal as it is fed back from the output of a circuit, device, or system to the input and then back to the output. Compare feedback loop.
2. Engineering.
   1. a processing system in which effluents are recycled, that is, treated and returned for reuse.
   2. an automatic control system operating on a feedback principle.
3. a recursive concept, process, or system in which there is no beginning or end point, but rather the products of one phase become the materials for the next, whose products themselves are the materials for the original phase:

   A circular economy is a closed loop, employing reuse, sharing, and remanufacturing to reduce waste.

4. Also called closed time loop. (in science fiction) a loop in space-time created by someone or something traveling back in time and setting in motion the events of the very timeline that leads to the time travel event, once again setting off events in the past that ultimately result in their being sent back in time, in an infinite, repeating loop.

closed-loop

²

[ klohzd-loop ]

adjective

1. Engineering.
   1. of or relating to a processing system in which effluents are recycled, that is, treated and returned for reuse.
   2. of or relating to an automatic control system operating on a feedback principle. feedback ( def 2 ).
2. of or relating to a recursive concept, process, or system in which there is no beginning or end point, but rather the products of one phase become the materials for the next, whose products themselves are the materials for the original phase:

   Around 75 percent of aluminum is kept out of landfills by closed-loop recycling, where used cans are pressed into ingots and rerolled into new cans, which can one day be recycled themselves.

Word History and Origins

Origin of closed loop¹

First recorded in 1945–50

Origin of closed loop²

First recorded in 1950–55

Example Sentences

Instead of an infinite string of distinct numbers, you end up in a small, closed loop.

From Quanta Magazine

On a less cosmic front, two mathematicians finally cracked an old problem in May about what kind of rectangles can be found by connecting points on a smooth and continuous closed loop.

From Quanta Magazine

Basically, we have a closed loop, and generate better and better images.

From Nautilus

With a lot of these, the full closed loop measurement hasn’t been set up.

From Digiday

The film includes beautifully clear descriptions and visualizations — for example, lines winding around a doughnut shape illustrate Mirzakhani’s study of the number of closed loops that can form on various curved surfaces.

From Science News

The system could operate on a closed loop, recycling its water and harnessing the power of the sun.

From The Daily Beast

The symbiotic relationship is part of what The Plant calls its closed-loop system.

From The Daily Beast

The "R" has a flat closed loop on the left side of the staff.

From Project Gutenberg

The ankh merely vibrates to evil because of the closed loop at the top, which makes a return circuit.

From Project Gutenberg

Thus, you see, magnetism produces electricity in the closed loop of wire as it cuts through the magnetic lines of force.

From Project Gutenberg

The f is longer than the , the g has a very fine form with a closed loop, the r is sharpened, the t straight.

From Project Gutenberg