arc

¹ American  

[ahrk] / ɑrk /

noun

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.

3. Astronomy. the part of a circle representing the apparent course of a heavenly body.

4. anything bow-shaped.

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verb (used without object)

arced, arcked, arcing, arcking

1. to form an electric arc.

2. to move in a curve suggestive of an arc.

ARC ² American  

[ahrk] / ɑrk /

noun

1. Pathology. AIDS-related complex.

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ARC ³ American  

Or A.R.C.

abbreviation

1. American Red Cross.

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arc ¹ British  

/ ɑːk /

noun

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

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verb

1. (intr) to form an arc

prefix

1. maths specifying an inverse trigonometric function: usually written arcsin , arctan , arcsec , etc, or sometimes sin–1 , tan–1 , sec–1 , etc

ARC ² British  

abbreviation

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

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arc Scientific  

/ ärk /

1. A segment of a circle.

2. See electric arc

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Etymology

Origin of arc

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

Example Sentences

“Before I was a woman who did comedy, and now I’m a man who does drama. I don’t know what happened there,” Gibson says laughing about the most surprising part of his own transition arc.

From Los Angeles Times • Apr. 1, 2026

Nor, unfortunately, does it reflect Martin Luther King’s hopeful idea that history’s arc ultimately bends towards justice.

From Salon • Mar. 28, 2026

The dam, which is 30% complete, was meant to be an architectural centerpiece—bowing outward, in defiance of standard engineering in which dams arc inward.

From The Wall Street Journal • Mar. 26, 2026

Unlike many freestyle rap hits, Children's Story was planned and written with a deliberate story arc.

From BBC • Mar. 25, 2026

In their jackets of bristling skins they seemed wild beasts rather than men, as they spread in a wide arc across the slope.

From "The Black Cauldron" by Lloyd Alexander

Related Words

• arch