from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A usually curved structure forming the upper edge of an open space and supporting the weight above it, as in a bridge or doorway.
  • noun A structure, such as a freestanding monument, shaped like an inverted U.
  • noun A curve with the ends down and the middle up.
  • noun Anatomy An organ or structure having a curved or bowlike appearance, especially either of two arched sections of the bony structure of the foot.
  • intransitive verb To provide with an arch.
  • intransitive verb To cause to form an arch or similar curve.
  • intransitive verb To bend backward.
  • intransitive verb To span.
  • intransitive verb To form an arch or archlike curve.
  • adjective Chief; principal.
  • adjective Mischievous; roguish.
  • adjective Teasing, ironic, or sardonic.

from The Century Dictionary.

  • To cover with a vault, or span with an arch.
  • To throw into the shape of an arch or vault; curve: as, the horse arches his neck.
  • To form an arch or arches: as, the sky arches overhead.
  • noun Chief; principal: a prefix much used in composition with words both of native and of foreign origin. See arch.
  • Chief; principal; preëminent. See arch-.
  • Cunning; sly; shrewd; waggish; mischievous for sport; roguish: now commonly used of facial expression: as, “so arch a leer,”
  • noun A chief; a leader.
  • noun A box or chest; in plural, archives.
  • noun The ark of Noah.
  • noun The ark of the covenant.
  • noun 1. In geometry, any part of the circumference of a circle or other curve; an arc. See arc
  • noun In architecture, a structure built of separate and inelastic blocks, assembled on a curved line in such a way as to retain their position when the structure is supported extraneously only at its two extremities.
  • noun Any place covered with an arch or a vault like an arch: as, to pass through the arch of a bridge.
  • noun Any curvature in the form of an arch: as, the arch of the aorta; the arch of an eyebrow, of the foot, of the heavens, etc.
  • noun In mining, a portion of a lode left standing, either as being too poor for profitable working or because it is needed to support the adjacent rock.
  • noun The roofing of the fire-chamber of a furnace, as a reverberatory or a glass-furnace; hence, sometimes, the fire-chamber itself.

from the GNU version of the Collaborative International Dictionary of English.

  • intransitive verb To form into an arch; to curve.
  • transitive verb To cover with an arch or arches.
  • transitive verb To form or bend into the shape of an arch.
  • noun obsolete A chief.
  • noun (Geom.) Any part of a curved line.
  • noun Usually a curved member made up of separate wedge-shaped solids, with the joints between them disposed in the direction of the radii of the curve; used to support the wall or other weight above an opening. In this sense arches are segmental, round (i. e., semicircular), or pointed.
  • noun A flat arch is a member constructed of stones cut into wedges or other shapes so as to support each other without rising in a curve.
  • noun Any place covered by an arch; an archway.
  • noun Any curvature in the form of an arch.
  • noun a monumental structure resembling an arched gateway, with one or more passages, erected to commemorate a triumph.
  • adjective Chief; eminent; greatest; principal.
  • adjective Cunning or sly; sportively mischievous; roguish.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective ​ Knowing, clever, mischievous.
  • adjective Principal; primary.
  • noun An inverted U shape.
  • noun An arch-shaped arrangement of trapezoidal stones, designed to redistribute downward force outward.
  • noun architecture An architectural element having the shape of an arch
  • noun archaic, geometry An arc; a part of a curve.
  • verb To form into an arch shape

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • verb form an arch or curve


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English, from Old French arche, from Vulgar Latin *arca, from Latin arcus.]

from The American Heritage® Dictionary of the English Language, 4th Edition

[From arch–.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From the prefix arch-. "Principal" is the original sense; "mischievous" is via onetime frequent collocation with rogue, knave, etc.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Middle English, from Old French arche ("an arch") (French arche), a feminine form of arc, from Latin arcus ("a bow, arc, arch").


Help support Wordnik (and make this page ad-free) by adopting the word arch.


  • MISCELLANEOUS WORDS. adobe _ado'ba_ algebra not _bra_ alien _alyen_, not _alien_ ameliorate _amelyorate_ antarctic _antarktik_ anti not _anti_ archangel _arkangel_ archbishop _arch_, not _ark_ arch fiend _arch_, not _ark_ architect _arkitect_ awkward _awkward_, not _ard_

    Practical Grammar and Composition Thomas Wood

  • Especially rich were the half-dome of the apse and the wall-space surrounding its arch and called the _triumphal arch_; next in decorative importance came the broad band of wall beneath the clearstory windows.

    A Text-Book of the History of Architecture Seventh Edition, revised 1890

  • The development of fan-vaulting had led to the adoption of a new form of arch, the four-centred or _Tudor arch_ (Fig. 133), to fit under the depressed apex of the vault.

    A Text-Book of the History of Architecture Seventh Edition, revised 1890

  • As late as the first half of the tenth century we meet with the term arch-acolyte in Luitprand of Cremona

    The Catholic Encyclopedia, Volume 1: Aachen-Assize 1840-1916 1913

  • The signification of the term arché, already used, was sufficiently comprehensive to include that of aitía, since all causes come necessarily under the head of principles.

    The Catholic Encyclopedia, Volume 3: Brownson-Clairvaux 1840-1916 1913

  • I particularly related to buying earrings on the street and to looking at how gorgeous the arch is at night.

    Nostalgia. « 2008

  • The base of the arch is a piece of hand-dyed fabric, with a large number of skeleton leaves attached with free motion quilting (mostly a meander with a few leaves and flowers thrown in).

    Blue flowery arch katelnorth 2008

  • I'm never too interested in monuments and touristy attractions, but I do think the arch is a very beautiful creation, rising sleekly into the sky at the bank of the Mississippi river, denoting the border between Missouri and Illinois.

    Archive 2007-05-01 Nupur 2007

  • I have big enough feet that I can fit into guys boots, but the arch is always in the wrong spot for me.

    Girl-ified Gear 2007

  • Sometimes interruption of the aortic arch is diagnosed on a fetal ultrasound and/or fetal echocardiogram.

    Interruption of the Aortic Arch 2010


Log in or sign up to get involved in the conversation. It's quick and easy.

  • The secondary definition is especially interesting:

    1. playfully roguish or mischievous: an arch smile.

    2. cunning; crafty; sly.

    January 28, 2007

  • Also, Professor Moriarty's way off the Holodeck.

    January 28, 2007

  • I like the sense of mischievous

    July 12, 2007

  • "He was also known for weaving together seemingly unrelated themes in an arch, self-deprecating way that helped break down the image of the critic as an all-knowing figure who wrote from atop a pedestal."

    The New York Times, October 3, 2007, Herbert Muschamp Obit

    October 4, 2007

  • I've seen this form used as an intransitive verb meaning "to engage in archery; to shoot a bow", as a backformation from "archery".

    October 27, 2010

  • It's what a pirate exclaims when he drops a cannonball on his toe.

    October 27, 2010

  • That pirate should have been wearing protective arch supports.

    October 27, 2010