Geometry . any unbroken part of the circumference of a circle or other curved line.

Also called electric arc. Electricity . a luminous bridge formed in a gap between two electrodes. Compare spark 1 ( def. 2 ) .

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

anything bow-shaped.

to form an electric arc.

to move in a curve suggestive of an arc.

adjective

arched , arciform , bowed , curved , curvilinear , rounded