From The Collaborative International Dictionary of English v.0.48:
Arc \Arc\ ([aum]rk), v. i. [imp. & p. p. Arcked ([aum]rkt); p.
pr. & vb. n. Arcking.] (Elec.)
To form a voltaic arc, as an electrical current in a broken
or disconnected circuit.
[Webster 1913 Suppl.]
From The Collaborative International Dictionary of English v.0.48:
Arc \Arc\, n. [F. arc, L. arcus bow, arc. See Arch, n.]
1. (Geom.) A portion of a curved line; as, the arc of a
circle or of an ellipse.
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2. A curvature in the shape of a circular arc or an arch; as,
the colored arc (the rainbow); the arc of Hadley's
quadrant.
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3. An arch. [Obs.]
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Statues and trophies, and triumphal arcs. --Milton.
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4. The apparent arc described, above or below the horizon, by
the sun or other celestial body. The diurnal arc is
described during the daytime, the nocturnal arc during the
night.
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Electric arc, Voltaic arc. See under Voltaic.
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