loop

plural loops

1. A length of thread, line or rope that is doubled over to make an opening.
2. The opening so formed.
3. A shape produced by a curve that bends around and crosses itself.

   Arches, loops, and whorls are patterns found in fingerprints.

4. A process that returns to its beginning and then repeats itself in the same sequence.

   time loop

   2 more examples

   feedback loop

   An online feed that constantly “refills” manipulates the brain’s dopaminergic reward system in a similar way. These powerful dopamine-driven loops of endless “seeking” can become addictive.

   2024 December 9, Siân Boyle, “Is doom scrolling really rotting our brains? The evidence is getting harder to ignore”, in The Guardian, archived from the original on 26 Feb 2026

   Synonyms: cycle

5. A ring road or beltway.
6. An endless strip of tape or film allowing continuous repetition.

   He can hang out in the back room of the local adult bookstore […] and hope for a stand-up blow-job through the glory hole in the partition of the two booths that show gay loops.

   1979 December 8, anonymous author, “The Small Town”, in Gay Community News, volume 7, number 20, page 5

7. A complete circuit for an electric current.
8. computingA programmed sequence of instructions that is repeated until or while a particular condition is satisfied.
9. graph theoryAn edge that begins and ends on the same vertex.
10. mathematicsA path that starts and ends at the same point.
11. transportA bus or rail route, walking route, etc. that starts and ends at the same point.
12. rail transportA place at a terminus where trains or trams can turn round and go back the other way without having to reverse; a balloon loop, turning loop, or reversing loop.

    In 1908 the line was extended to a station called Wood Lane, which was built on a terminal track loop so that trains could turn round and go back the other way, [...]

    2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, →ISBN, page 119

13. rail transportA passing loop.

    Basingstoke-Exeter will test this. From Salisbury westwards, it's largely single-track since British Rail downgraded it in 1967. There's a ten-mile loop between Templecombe and Yeovil, as well as shorter loops at Chard, Axminster and Honiton.

    2025 February 5, Philip Haigh, “Where track and train integration will be put to the test”, in RAIL, number 1028, page 51

14. algebraA quasigroup with an identity element.
15. A loop-shaped intrauterine device.
16. An aerobatic maneuver in which an aircraft flies a circular path in a vertical plane.
17. A small, narrow opening; a loophole.

    And stop all sight-holes, every loop from whence / The eye of Reason may pry in upon us.

    c. 1597 (date written), William Shakespeare, “The First Part of Henry the Fourth, […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act IV, scene i]

18. alternativeAlternative form of loup (“mass of iron”).
19. biochemistryA flexible region in a protein's secondary structure.
20. CanadaUSdatedhobbiesA sports league

    Arellano formerly cavorted for the Galicias in the fast-paced National-American Soccer loop.

    1963 September 27, “Italias Vie In Bayonne On Sunday”, in The Jersey Journal, page 17

21. ball gamesThe curved path of the ball bowled by a spin bowler.

present singular third person loops · participle present looping · participle past looped · past looped

1. transitiveTo form something into a loop.
2. transitiveTo fasten or encircle something with a loop.
3. transitiveTo fly an aircraft in a loop.
4. transitiveTo move something in a loop.
5. transitiveTo play something (such as a song or video) in a loop.
6. transitiveTo join electrical components to complete a circuit.
7. transitiveTo duplicate the route of a pipeline.
8. transitiveTo create an error in a computer program so that it runs in an endless loop and the computer freezes up.
9. intransitiveTo form a loop.
10. intransitiveTo move in a loop.

    The program loops until the user presses a key.

    1 more example

    The outstanding Tom Palmer won a line-out and then charged into the heart of the Welsh defence, scrum-half Ben Youngs moved the ball swiftly right and Cueto's looping pass saw Ashton benefit from a huge overlap to again run in untouched.

    2011 February 4, Gareth Roberts, “Wales 19-26 England”, in BBC

11. To place in a loop.

    It found that trains often looped on their journey emit 14% to 20% more NOx and particulates than non-stop services.

    2021 January 13, Richard Clinnick, “Longer freight trains boost efficiency and reduce carbon”, in Rail, page 10

12. ambitransitiveeducationTo have the teacher progress through multiple school years with the same students.

    Tolland Middle School in Connecticut where close to four hundred middle school students participated in looping, students from looped classroom structures scored much higher than students from prior years without the looped structure on standardized tests in mathematics and writing.

    2003, Lisa Lynn Snyder, An Investigation of Elementary Looping Practices and Outcomes in a Rural School District, page 54

plural Loops

1. A surname.
2. informalsingularMelbourneThe City Loop.

   Does this train go through the Loop?

1. abbreviationacronymAcronym of loss of offsite power.