\ ˈärch How to pronounce arch (audio) \

Essential Meaning of arch

1 : a usually curved part of a structure that is over an opening and that supports a wall or other weight above the opening
2 : the raised area on the bottom of the foot that is formed by a curved section of bones
3 : something that has a curved shape There was a slight arch to her eyebrows. an arch in the cat's back

Full 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
3 : archway


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)


prefix (1)

Definition of arch- (Entry 6 of 9)

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


prefix (2)

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

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 The luff along the edges, the abundance of wind along the reach of the river, the arch and tip of the boat in relation to the air and the water; a boy, one hand on his tiller, the other on the rope, ducking down but not far enough. David Means, Harper's Magazine, 23 Nov. 2021 The 5-foot-5-inch senior averaged 12.7 points, 4.2 rebounds, 3.5 assists and four steals per game and shot 48% inside the arch and 32% outside it. Melanie Laughman, The Enquirer, 19 Nov. 2021 The doors serve as protection, especially against their predatory arch nemesis: parasitic wasps. Shi En Kim, Smithsonian Magazine, 27 Oct. 2021 His characters tend to be unstable but charming, his writing arch and deadpan. Anna Altman, The New Republic, 11 Nov. 2021 And how will dearly departed, fourth season arch-foe, The Trinity Killer rise? Bryan Alexander, USA TODAY, 5 Nov. 2021 In addition to the amphitheater, archaeologists have discovered the ruins of a triumphal arch and other structures in and around Richborough. David Kindy, Smithsonian Magazine, 4 Nov. 2021 Tucci is trim, gently muscled, bespectacled, a little arch, a little icy. Helen Rosner, The New Yorker, 31 Oct. 2021 This was his prize for scoring a brilliant hat-trick to help Liverpool record their biggest win over their arch-rivals for nearly a century. Sam Pilger, Forbes, 28 Oct. 2021 Recent Examples on the Web: Verb The durable fit of this slip-on provides heel stability and arch support, while a removable dual-density footbed ensures total comfort. Claire Harmeyer,, 4 Nov. 2021 With forefoot cushioning and arch support midsole, these promote stability and help relieve foot issues like bunions and plantar fasciitis. Claire Harmeyer,, 4 Nov. 2021 The Mitchell Park Horticultural Conservatory — better known as The Domes — arch into the sky and house a trio of vegetation exhibits: a desert oasis, a tropical jungle and a floral garden. Jr Radcliffe, Milwaukee Journal Sentinel, 11 Oct. 2021 The leaves arch but remain upright, allowing close spacing between bulbs — four inches or so. Adrian Higgins, Washington Post, 20 Sep. 2021 The secret to a perfect shape is learning where your brows should start, arch and end. Felicity Carter, Forbes, 13 Sep. 2021 Her heart does not arch toward them; her torso doesn't lean in and surround. Olivia Harrison,, 8 June 2021 Bertrand represents a new and potent type of figure in the Party, the arch-articulate young woman who pits women’s rights against Muslim immigration. Isaac Chotiner, The New Yorker, 12 Aug. 2021 Anyone else see acres of empty seats at TQL Stadium and arch an eyebrow? Paul Daugherty, The Enquirer, 11 Aug. 2021 Recent Examples on the Web: Adjective Kant’s usually vilified as somewhat of an arch rationalist, in fact, no? Isaac Chotiner, The New Yorker, 24 Nov. 2021 Carole Baskin also took aim Thursday at her arch nemesis Joe Exotic, former owner of the roadside G.W. Zoo, who is in prison for organizing a murder-for-hire scheme against his rival as well as for animal abuse. Christi Carras, Los Angeles Times, 18 Nov. 2021 No longer an arch expression of chicness, black has become inexplicably associated with the desire to disappear. Isabel Slone, Harper's BAZAAR, 1 Nov. 2021 Even with grand scene-stealing characters like Wint or Belle, the humor is natural, not arch. Christopher Arnott,, 25 Oct. 2021 Nick did just agree to have an alliance with Kai, his arch nemesis, and if there was ever a moment to get her out, it’s now. Paul Tassi, Forbes, 17 Sep. 2021 While most of the attention in Sheppard's recruitment has been directed at his parent's alma mater, Kentucky's arch rival made an early effort to land him as well. Jon Hale, The Courier-Journal, 17 Nov. 2021 Hamilton beat its arch rival for for the first time since 2013. Richard Obert, The Arizona Republic, 14 Nov. 2021 And don’t be surprised if the Boston Red Sox enter the bidding – essentially to prevent Marte from signing with the arch-rival Yankees. Dan Schlossberg, Forbes, 13 Nov. 2021

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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Dictionary Entries Near arch

arc furnace



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Last Updated

2 Dec 2021

Cite this Entry

“Arch.” Dictionary, Merriam-Webster, Accessed 6 Dec. 2021.

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More Definitions for arch


\ 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

More from Merriam-Webster on arch

Nglish: Translation of arch for Spanish Speakers

Britannica English: Translation of arch for Arabic Speakers Encyclopedia article about arch


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