# loop
## English
### Etymology

From Middle English loupe (“noose, loop”), earlier lowp-knot (“loop-knot”), of North Germanic origin, from Old Norse hlaup (“a run”), used in the sense of a "running knot", from hlaupa (“to leap”), ultimately from Proto-Germanic *hlaupaną (“to leap, run”). Compare Swedish löp-knut (“loop-knot”), Danish løb-knude (“a running knot”), Danish løb (“a course”). More at leap. The verb is derived from the noun.

### Pronunciation

* IPA: /luːp/
* Rhymes: -uːp
* Homophone: loupe
* Audio (Southern England):(file)

### Noun

loop (plural loops)
* A length of thread, line or rope that is doubled over to make an opening.
* The opening so formed.
* A shape produced by a curve that bends around and crosses itself.
    Arches, loops, and whorls are patterns found in fingerprints.
* A ring road or beltway.
* An endless strip of tape or film allowing continuous repetition.
** 1979 December 8, anonymous author, “The Small Town”, in Gay Community News, volume 7, number 20, page 5: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.
* A complete circuit for an electric current.
* (programming) A programmed sequence of instructions that is repeated until or while a particular condition is satisfied.
* (graph theory) An edge that begins and ends on the same vertex.
* (topology) A path that starts and ends at the same point.
* (transport) A bus or rail route, walking route, etc. that starts and ends at the same point.
* (rail transport) A 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.
** 2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, →ISBN, page 119: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, [...]
* (rail transport) A passing loop.
** 2025 February 5, Philip Haigh, “Where track and train integration will be put to the test”, in RAIL, number 1028, page 51: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.
* (algebra) A quasigroup with an identity element.
* A loop-shaped intrauterine device.
* An aerobatic maneuver in which an aircraft flies a circular path in a vertical plane.
* A small, narrow opening; a loophole.
** 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]:And stop all sight-holes, every loop from whence / The eye of Reason may pry in upon us.
* Alternative form of loup (“mass of iron”)
* (biochemistry) A flexible region in a protein's secondary structure.
* (Canada, US, dated, sports) A sports league
** 1963 September 27, “Italias Vie In Bayonne On Sunday”, in The Jersey Journal, page 17:Arellano formerly cavorted for the Galicias in the fast-paced National-American Soccer loop.
* (cricket) The curved path of the ball bowled by a spin bowler.

#### Hypernyms

* control structure

#### Hyponyms

* balloon loop
* crossing loop
* endless loop
* event loop
* feedback loop
* for loop
* hanging loop
* infinite loop
* inside loop
* main loop
* message loop
* passing loop
* platform loop
* read-eval-print loop
* reconciliation loop
* reversing loop
* run loop
* self-loop
* span loop
* tight loop
* while loop

#### Derived terms

* A-B loop
* adjustable loop
* angler's loop
* artillery loop
* autoregulatory loop
* belt loop
* boot loop
* busy loop
* closed loop
* closed time loop
* close the loop
* compulsion loop
* core loop
* crossed loop sensor
* death loop
* do loop
* doom loop
* do-while loop
* edge loop
* fisherman's loop
* foreach loop
* fruit loop
* ground loop
* harness loop
* hearing loop
* Henle loop
* Henle's loop
* hysteresis loop
* induction loop
* keep someone in the loop
* Latham loop
* launch loop
* Lebanese loop
* Lippes loop
* local loop
* locker loop
* Lofstrom loop
* loop de loop
* loop-de-loop
* loop disconnect dialing
* loop diuretic
* loophole
* loop hole
* loop invariant
* loop jump
* loop line, loopline
* loop of Henle
* loop pedal
* loop quantum gravity
* loop ratio
* loop-the-loop
* loop-top
* loop transfer function
* loop-window
* Möbius loop
* Moufang loop
* Murray loop bridge
* open-loop
* Orowan loop
* outside loop
* penalty loop
* phase-locked loop
* service loop
* small loop
* stem-loop
* strange loop
* throw for a loop
* time loop
* toe loop
* ulnar loop
* Varley loop
* Wilson loop

#### Related terms

* hook-and-loop
* hook-and-loop fastener
* in the loop
* knock for a loop
* loop antenna
* loop the loop
* out of the loop
* time-loop logic

#### Translations

    The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

### Verb

loop (third-person singular simple present loops, present participle looping, simple past and past participle looped)
* (transitive) To form something into a loop.
* (transitive) To fasten or encircle something with a loop.
* (transitive) To fly an aircraft in a loop.
* (transitive) To move something in a loop.
* (transitive) To join electrical components to complete a circuit.
* (transitive) To duplicate the route of a pipeline.
* (transitive) To create an error in a computer program so that it runs in an endless loop and the computer freezes up.
* (intransitive) To form a loop.
* (intransitive) To move in a loop.
    The program loops until the user presses a key.
** 2011 February 4, Gareth Roberts, “Wales 19-26 England”, in BBC‎: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.
* To place in a loop.
** 2021 January 13, Richard Clinnick, “Longer freight trains boost efficiency and reduce carbon”, in Rail, page 10:It found that trains often looped on their journey emit 14% to 20% more NOx and particulates than non-stop services.
* (education, ambitransitive) To have the teacher progress through multiple school years with the same students.
** 2003, Lisa Lynn Snyder, An Investigation of Elementary Looping Practices and Outcomes in a Rural School District, page 54: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.

#### Derived terms

* loopback
* loop in
* loop the loop
* loop up

#### Translations
### See also

* Appendix:Parts of the knot

### References

* loop on Wikipedia.Wikipedia

### Anagrams

* OOPL, Polo, Pool, polo, pool

## Afrikaans
### Pronunciation

* IPA: /lʊəp/

### Etymology 1

From Dutch lopen, from Middle Dutch lôpen, from Old Dutch lōpan, from Proto-West Germanic *hlaupan, from Proto-Germanic *hlaupaną (“to run”).

#### Verb

loop (present loop, present participle lopende, past participle geloop)
* (intransitive) to walk

##### Alternative forms

* loep (Western Cape)

### Etymology 2

From Dutch loop, from Middle Dutch lôop, from Old Dutch *lōp.

#### Noun

loop (plural lope, diminutive lopie)
* walking, gait
* (of events) course
* (of guns) barrel
* (informal) business end (of a rifle, etc.)
* (music, usually in diminutive) run: a rapid passage in music, especially along a scale

## Chinese
### Etymology

From English loop.

### Pronunciation

* Cantonese (Jyutping): lup$^1$
* Cantonese
** (Standard Cantonese, Guangzhou–Hong Kong)
*** Jyutping: lup$^1$
*** Cantonese Pinyin: lup$^7$
*** Sinological IPA : /luːp̚⁵/

### Verb

loop
* (Hong Kong Cantonese) to repeatedly consume or play songs or videos
       tiu$^4$ pin$^3$ ngo$^5$ lup$^1$ zo$^2$ gei$^2$ baak$^3$ ci$^3$ [Jyutping]
       I've repeatedly watched the video a few hundreds times
* (Hong Kong Cantonese, by extension) to occur repeatedly

### Noun

loop
* (Hong Kong Cantonese) loop; cycle (Classifier: 個／个 c)
    無限loop／无限loop [Cantonese] ― mou$^4$ haan$^6$ lup$^1$ [Jyutping] ― infinite never-ending loop

## Dutch
### Pronunciation

* IPA: /loːp/
* Audio:(file)
* Hyphenation: loop
* Rhymes: -oːp

### Etymology 1

From Middle Dutch lôop, from Old Dutch *lōp, from Proto-West Germanic *hlaup, from Proto-Germanic *hlaupą. Equivalent to a deverbal from lopen (“to walk”).

#### Noun

loop m (plural lopen, diminutive loopje n)
* course, duration
* a river course
* course of a projectile
* barrel (of a firearm)

##### Derived terms

* afloop
* kanonsloop
* kringloop
* levensloop
* loopbaan
* sponsorloop
* verloop
* wedloop

##### Related terms

* lopen

##### Descendants

* Afrikaans: loop
* → Indonesian: lop
* → Lokono: loporo
* → Papiamentu: lop

### Etymology 2

See the etymology of the corresponding lemma form.

#### Verb

loop
* inflection of lopen:
** first-person singular present indicative
** (in case of inversion) second-person singular present indicative
** imperative

### Anagrams

* Pool, pool

## Portuguese
### Etymology

Unadapted borrowing from English loop.

### Pronunciation

* (Brazil) IPA: /ˈlu.pi/, /ˈlup/
* (Brazil) IPA: /ˈlu.pi/, /ˈlup/
** (Southern Brazil) IPA: /ˈlup/, /ˈlu.pi/
* (Portugal) IPA: /ˈlup/

### Noun

loop m (plural loops)
* (computing) loop (repeating sequence of instructions)
    Synonyms: ciclo, laço
* loop (aircraft manoeuvre)
    Synonym: looping

#### Derived terms

* in loop