arc

An arc is a curve. You can describe the bend of a rainbow as an arc.

In math, an arc is one section of a circle, but in life you can use the word to mean any curved shape, like the arc of a ballerina's arm or the graceful arc of a flowering vine over a trellis. In the 14th century, arc first meant the movement of the sun in the sky, from the Old French arc, "bow or arch," and the Latin root arcus, also "bow or arch."

Definitions of arc
  1. noun
    a continuous portion of a circle
    see moresee less
    types:
    limb
    the graduated arc that is attached to an instrument for measuring angles
    type of:
    curve, curved shape
    the trace of a point whose direction of motion changes
  2. noun
    something curved in shape
    synonyms: bow
    see moresee less
    types:
    rainbow
    an arc of colored light in the sky caused by refraction of the sun's rays by rain
    type of:
    curve, curved shape
    the trace of a point whose direction of motion changes
  3. verb
    form an arch or curve
    synonyms: arch, curve
    see moresee less
    types:
    camber
    curve upward in the middle
    type of:
    bend, flex
    form a curve
  4. noun
    electrical conduction through a gas in an applied electric field
    synonyms: discharge, electric arc, electric discharge, spark
    see moresee less
    types:
    brush discharge
    discharge between electrodes creating visible streamers of ionized particles
    Saint Elmo's fire, Saint Elmo's light, Saint Ulmo's fire, Saint Ulmo's light, St. Elmo's fire, corona, corona discharge, corposant, electric glow
    an electrical discharge accompanied by ionization of surrounding atmosphere
    flashover
    an unintended electric discharge (as over or around an insulator)
    type of:
    electrical conduction
    the passage of electricity through a conductor
Word Family