brush discharge - discharge between electrodes creating visible streamers of ionized particles

corona discharge, corposant, electric glow, Saint Elmo's fire, Saint Elmo's light, Saint Ulmo's fire, Saint Ulmo's light, St. Elmo's fire, corona - an electrical discharge accompanied by ionization of surrounding atmosphere

flashover - an unintended electric discharge (as over or around an insulator)

electrical conduction - the passage of electricity through a conductor

limb - the graduated arc that is attached to an instrument for measuring angles; "the limb of the sextant"

curve, curved shape - the trace of a point whose direction of motion changes

circle - ellipse in which the two axes are of equal length; a plane curve generated by one point moving at a constant distance from a fixed point; "he calculated the circumference of the circle"

sector - a plane figure bounded by two radii and the included arc of a circle

rainbow - an arc of colored light in the sky caused by refraction of the sun's rays by rain

curve, curved shape - the trace of a point whose direction of motion changes

camber - curve upward in the middle

bend, flex - form a curve; "The stick does not bend"