1. (n.) A portion of a curved line; as, the arc of a circle or of an ellipse.
2. (n.) A curvature in the shape of a circular arc or an arch; as, the colored arc (the rainbow); the arc of Hadley's quadrant.
3. (n.) An arch.
4. (n.) 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.
Thesaurus Entries
AC arc, Poulsen arc, aperiodic discharge, arc column, arc discharge, arc light, arch, bend, bow, brush discharge, catacaustic, catenary, caustic, circle, color filter, conchoid, crook, curl, curvation, curvature, curve, diacaustic, dimmer, discharge, disruptive discharge, electric discharge, electric shock, electric spark, electrodeless discharge, ellipse, festoon, floats, flood, floodlight, footlights, foots, galvanic shock, gelatin, glow discharge, hook, hyperbola, klieg light, light plot, lights, limelight, lituus, marquee, medium, oscillatory discharge, parabola, round, shock, silent discharge, sinus, spark, spark gap, spot, spotlight, tracery
