\ ˈärch How to pronounce arch (audio) \

Definition of arch

 (Entry 1 of 9)

1 : a typically curved structural member spanning an opening and serving as a support (as for the wall or other weight above the opening)
2a : something resembling an arch in form or function especially : either of two vaulted portions of the bony structure of the foot that impart elasticity to it
b : something that has a curved shape like an arch There was a slight arch in her eyebrows. an arch in the cat's back


arched; arching; arches

Definition of arch (Entry 2 of 9)

transitive verb

1 : to cover or provide with an arch A bridge arches the stream.
2 : to form into an arch She arched her eyebrows.

intransitive verb

1 : to form an arch Trees arch above the promenade.
2 : to take an arch-shaped course The ball arched toward the basket.

Definition of arch (Entry 3 of 9)

1 : principal, chief your arch opponent/rival an arch enemy
b : marked by a deliberate and often forced playfulness, irony, or impudence known for her arch comments … decided to answer them by being teacherly in a sort of arch, Olympian way.— Gerald Early

Definition of arch (Entry 4 of 9)

Definition of Arch (Entry 5 of 9)

Definition of arch- (Entry 6 of 9)

1 : chief : principal archfiend
2 : extreme : most fully embodying the qualities of the kind archconservative

Definition of arch- (Entry 7 of 9)

— see archi-

Definition of -arch (Entry 8 of 9)

: ruler : leader matriarch

Definition of -arch (Entry 9 of 9)

: having (such) a point or (so many) points of origin endarch

Illustration of arch

Illustration of arch


arch 1: 1 round: imp impost, sp springer, v voussoir, k keystone, ext extrados, int intrados; 2 horseshoe; 3 lancet; 4 ogee; 5 trefoil; 6 basket-handle; 7 Tudor

In the meaning defined above

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Other Words from arch


archness noun

Did You Know?


As a prefix, arch- appears in a number of titles referring to positions of superiority, such as archduke and archbishop. Ultimately deriving (via Latin and French) from the Greek verb archein ("to begin, rule"), it can also mean "chief " (as in archnemesis) or "extreme" (as in archconservative). In the 17th century, as the "extreme" sense of arch came to be used frequently to describe rogues, knaves, and other clever and mischievous sorts, arch eventually settled into use as an adjective to describe one with impish or playful qualities. Use of the word has since extended to describe actions or remarks meant to be ironic, cutting, or condescending.

Examples of arch in a Sentence

Noun There was a slight arch to her eyebrows. an arch in the cat's back Verb The cat arched its back. She arched her eyebrows in surprise. A tree arches over the road. She arched backward to begin the exercise. Adjective a politician known for his arch humor The novel is never mocking or arch in its tone.
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Recent Examples on the Web: Noun Two other neighbors also got Christmas trees to put on either side of the large, sparkling arch. Paige Fry,, "‘Chance made us neighbors. ... Quarantine made us family’: Albany Park residents come together for arch display to cheer up a coronavirus Christmas," 25 Dec. 2020 Careerism, not community, is the keystone in the arch of life. Derek Thompson, The Atlantic, "How Civilization Broke Our Brains," 13 Dec. 2020 Another is a painting by his 25-year-old daughter, Schuyler, of a stone arch in Utah. Charles Trepany, USA TODAY, "Michael J. Fox reveals scariest moment of risky surgery in 'No Time Like the Future'," 17 Nov. 2020 This mini text-adventure takes place in an institution for disabled veterans where the two arch-enemies meet. Andrada Fiscutean, Ars Technica, "How Indiana Jones, Rambo, and others ended up in 1980s Czechoslovak text-adventures," 23 Oct. 2020 Pause at the top, and really squeeze your butt to ensure that your hip flexors are completely extended (your legs are straight), and your pelvis is stacked directly under your shoulders, with no arch in your low back. Amy Eisinger, M.a., SELF, "How to Do a Deadlift Correctly," 4 Jan. 2021 That’s a much more substantial arch than a typical curved display, which usually clocks in around 1,800R. Stan Horaczek, Popular Science, "The best gadgets of 2020," 2 Dec. 2020 The entrance is an inconspicuous little arch, guarded by an antique wrought-iron gate, between a fine wine shop and a musty bookstore. Kurt Vonnegut, The New Yorker, "Letters to Woofy," 23 Nov. 2020 That led to the graceful arch, which the duo echoed in the shower doorway. Hadley Keller, House Beautiful, "Toledo Geller Turns a Drab Spare Room Into a Dreamy (and Super Functional), Moroccan-Inspired Bathroom," 29 Sep. 2020 Recent Examples on the Web: Verb Florida Gators legend Steve Spurrier once mockingly referred to arch rival FSU as Free Shoes U., but now UF has its own infamous footwear moniker. Mike Bianchi,, "After historic blunder, Gators should be renamed FSU — Fling Shoe U | Commentary," 13 Dec. 2020 Arizona has fired head football coach Kevin Sumlin, a day after the Wildcats lost 70-7 to arch-rival Arizona State and fell to 0-5 this season. Creg Stephenson |, al, "Arizona fires Kevin Sumlin, one day after 70-7 loss to Arizona State," 12 Dec. 2020 Even then a striped skunk usually will stomp his feet, arch his back and even hiss before spraying. René A. Guzman,, "Striped skunks: these little stinkers also help keep pests under control around San Antonio homes and are sweet and docile," 27 Oct. 2020 Bankside weeds and grasses have also reached their maximum height and droop over the bank low to the water, forming arch-like tunnels that give trout shade and cover. Popular Science, "A beginner’s guide to catching trout—even in autumn," 26 Oct. 2020 In terms of comfort, the Forever Sneaker has a thin insole and its flat design doesn’t lend too much to arch support. Kai Burkhardt, CNN Underscored, "Everlane’s new recyclable shoe is good for the planet — and your closet," 22 Oct. 2020 The most charming and welcoming gardens have climbing roses that arch over and define entry gates; spill over arbors, pillars and pergolas; cover walls, fences and trellises; or cascade down in a profusion of blooms from trees and hillsides. Rita Perwich, San Diego Union-Tribune, "Reach new heights in your rose garden with ramblers and climbers," 3 Oct. 2020 In The Disputa, from 1509–10, his figures are balletic, refined, even arch. Brian T. Allen, National Review, "The Immovable Raphael," 19 Sep. 2020 One of the trilithons (arch-like structures made of two upright stones supporting a horizontal lintel stone) in the central horseshoe fell down in 1797. Kiona N. Smith, Ars Technica, "Archaeologists find the source of Stonehenge sarsen stones," 30 July 2020 Recent Examples on the Web: Adjective The arch support and dual-density midsole kept us fresh after a strenuous eight-mile loop. The Popular Mechanics Editors, Popular Mechanics, "Gear of the Year: The Best Products We Tested in 2020," 29 Dec. 2020 Not only are these stylish and colorful, but Petkov says these shoes provide arch support and additional cushion. Lindsay Tigar, CNN Underscored, "19 gifts the runner in your life will appreciate, according to experts," 10 Dec. 2020 More expensive models will generally provide better arch support as well as premium insulation. The Editors, Field & Stream, "Three Things to Know Before Buying Winter Boots for Your Kids," 22 Aug. 2019 Immediacy was the goal, not the arch irony of its 1990s releases. George Varga, San Diego Union-Tribune, "All boxed up! New CD and vinyl box sets from Prince, Joni Mitchell, Frank Zappa, U2 and more," 13 Dec. 2020 Herman, 45, is 31-18 in four seasons at Texas, but has not won a Big 12 Conference championship and is 1-4 vs. arch-rival Oklahoma. Creg Stephenson |, al, "Texas sticking with Tom Herman as football coach, AD says," 12 Dec. 2020 Both programs prepare all season to beat its arch-rival, and in Navy’s case this year, a victory over Army would turn a disappointing 3-6 season into an unquestioned success. C.j. Doon,, "College football storylines, Week 15: In a year of lost rivalry games, at least we have Army-Navy," 11 Dec. 2020 The Mustangs, who overcame a 1-3 start to finish 6-4 this fall, went 4-2 against arch-rival Apopka under Bedesem — snapping a string of 12 consecutive losses to the Blue Darters after Wekiva opened. J.c. Carnahan,, "Wekiva fires football coach following playoff altercation; joining vacancies at Lyman, Tohopekaliga," 7 Dec. 2020 And now as fate would have it, Hopkins is about to meet up with his arch rival, Rams cornerback Jalen Ramsey, when the two superstars square off in a showdown this Sunday at State Farm Stadium. Bob Mcmanaman, The Arizona Republic, "Rivalry Renewed: Get popcorn ready for Cardinals' DeAndre Hopkins vs. Rams' Jalen Ramsey," 3 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'arch.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of arch


13th century, in the meaning defined at sense 2a


15th century, in the meaning defined at transitive sense 1


1547, in the meaning defined at sense 1

History and Etymology for arch

Noun and Verb

Middle English arche, from Anglo-French, from Vulgar Latin *arca, from Latin arcus — more at arrow


arch- entry 1

Prefix (1)

Middle English arche-, arch-, from Old English & Anglo-French; Old English arce-, from Late Latin arch- & Latin archi-; Anglo-French arch-, from Late Latin arch- & Latin archi-, from Greek arch-, archi-, from archein to begin, rule; akin to Greek archē beginning, rule, archos ruler

Noun combining form

Middle English -arche, from Anglo-French & Late Latin & Latin; Anglo-French -arche, from Late Latin -archa, from Latin -arches, -archus, from Greek -archēs, -archos, from archein

Adjective combining form

probably from German, from Greek archē beginning

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Time Traveler for arch

Time Traveler

The first known use of arch was in the 13th century

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Statistics for arch

Last Updated

24 Jan 2021

Cite this Entry

“Arch.” Dictionary, Merriam-Webster, Accessed 25 Jan. 2021.

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More Definitions for arch


How to pronounce -arch (audio)

English Language Learners Definition of arch

 (Entry 1 of 3)

: a usually curved part of a structure that is over an opening and that supports a wall or other weight above the opening
: the raised area on the bottom of the foot that is formed by a curved section of bones
: something that has a curved shape



English Language Learners Definition of arch (Entry 2 of 3)

: to bend into the shape of an arch

English Language Learners Definition of arch (Entry 3 of 3)

: having or showing an amused feeling of being superior to or knowing more than other people


\ ˈärch How to pronounce arch (audio) \

Kids Definition of arch

 (Entry 1 of 3)

1 : a usually curved part of a structure that is over an opening and serves as a support (as for the wall above the opening)
2 : something that has a curved shape like an arch the arch of the foot

Other Words from arch

arched \ ˈärcht \ adjective an arched doorway


arched; arching

Kids Definition of arch (Entry 2 of 3)

1 : to form or shape into an arch : curve The cat arched her back.
2 : to cover with an arch Tree branches arched the narrow road.

Kids Definition of arch (Entry 3 of 3)

1 : chief entry 2 sense 2, principal an arch opponent
2 : being clever and mischievous an arch look

Other Words from arch

archly adverb


\ ˈärch How to pronounce arch (audio) \

Medical Definition of arch

1 : an anatomical structure that resembles an arch in form or function: as
a : either of two vaulted portions of the bony structure of the foot that impart elasticity to it:
(1) : a longitudinal arch supported posteriorly by the basal tuberosity of the calcaneus and anteriorly by the heads of the metatarsal bones
(2) : a transverse arch consisting of the metatarsals and first row of tarsals and resulting from elevation of the central anterior portion of the median longitudinal arch
2 : a fingerprint in which all the ridges run from side to side and make no backward turn

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