A discharge of electricity across a gap that causes ionization of the air (or other gas) resulting in a bright, hot plasma

Third-person singular simple present indicative form of arc up

simple past tense and past participle of arc up

(Australia, slang) To become upset or angry.

(astronomy) The arc of a circle described by the Sun, or a star, in the night.

plural of nocturnal arc

An optical phenomenon, a large, brightly spectrum-coloured band running parallel to the horizon, formed by the refraction of sunlight or moonlight in plate-shaped ice crystals suspended in the atmosphere, typically in cirrus or cirrostratus clouds.

plural of circumhorizontal arc

plural of carbon arc

plural of electric arc