1. Geometry. any unbroken part of the circumference of a circle or other curved line.
  2. Also called electric arc. Electricity. a luminous bridge formed in a gap between two electrodes.Compare spark1(def 2).
  3. Astronomy. the part of a circle representing the apparent course of a heavenly body.
  4. anything bow-shaped.
verb (used without object), arced [ahrkt] /ɑrkt/ or arcked, arc·ing [ahr-king] /ˈɑr kɪŋ/ or arck·ing.
  1. to form an electric arc.
  2. to move in a curve suggestive of an arc.

Origin of arc

1350–1400; Middle English ark < Latin arcus bow, arch, curve
Can be confusedarc ark


  1. Pathology. AIDS-related complex.


  1. Associate of the Royal College of Science.
  2. Associate of the Royal College of Surgeons. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for arcs

arch, curvature, bow, crescent, round, bend, half-moon

Examples from the Web for arcs

Contemporary Examples of arcs

Historical Examples of arcs

British Dictionary definitions for arcs


abbreviation for
  1. Associate of the Royal College of Science


  1. something curved in shape
  2. part of an unbroken curved line
  3. a luminous discharge that occurs when an electric current flows between two electrodes or any other two surfaces separated by a small gap and a high potential difference
  4. astronomy a circular section of the apparent path of a celestial body
  5. maths a section of a curve, graph, or geometric figure
verb arcs, arcing, arced, arcs, arcking or arcked
  1. (intr) to form an arc
  1. maths specifying an inverse trigonometric function: usually written arcsin, arctan, arcsec, etc, or sometimes sin –1, tan –1, sec –1, etc

Word Origin for arc

C14: from Old French, from Latin arcus bow, arch


abbreviation for
  1. AIDS-related complex: an early condition in which a person infected with the AIDS virus may suffer from such mild symptoms as loss of weight, fever, etc
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for arcs



late 14c., originally in reference to the sun's apparent motion in the sky, from Old French arc "bow, arch, vault" (12c.), from Latin arcus "a bow, arch," from PIE root *arku- "bowed, curved" (cf. Gothic arhvazna "arrow," Old English earh, Old Norse ör; also, via notion of "supple, flexible," Greek arkeuthos, Latvian ercis "juniper," Russian rakita, Czech rokyta, Serbo-Croatian rakita "brittle willow"). Electrical sense is from 1821.



1893, in the electrical sense, from arc (n.). Meaning "to move in an arc" attested by 1954. Related: Arced; arcing.

Online Etymology Dictionary, © 2010 Douglas Harper

arcs in Medicine


  1. A curved line or segment of a circle.


  1. AIDS-related complex
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

arcs in Science


  1. A segment of a circle.
  2. See electric arc.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.