General Science

  • noun a part of the circumference of a circle, or the shape of this

Cars & Driving


  • The electrical discharge between two electrodes. When the electrodes are surrounded by gas in a lamp, they become a bright, economical light source.
  • Any portion of a circle or the angle that it makes.


  • A highly luminous and sustained discharge of electricity between two conductors separated by a gas. It is characterized by a high current density and a low voltage drop. Used, for example, in welding and arc lamps. This contrasts with a spark, which has a short duration. Also known as electric arc.
  • A continuous part of a curve.

Media Studies

  • noun a type of powerful light used for filming
  • verb to change the size or shape of a picture using an aspect ratio converter
  • acronym foraspect ratio converter
    (written as ARC)
  • noun a device for converting pictures into a form that can be shown on a screen with a different aspect ratio.


  • noun a nerve pathway
  • noun part of a curved structure in the body
  • acronym forAIDS-related complex
    (written as ARC)
  • acronym forAIDS-related condition
    (written as ARC)
  • noun early symptoms shown by someone infected with the HIV virus, e.g. weight loss, fever and herpes zoster.


  • Informal name for a carbon arc spotlight, the earliest formof electric lighting used in theaters. Employing two carbonelectrodes, it provided an intense (though flickering) beam. The arcwas invented in 1809 by Sir Humphry Davy, who also helped developthe limelight. It was used as an experiment in an 1846 productionof Proph├Ęte at the Paris Opera but did not come intogeneral theatrical use until about 1870. By the 1880s the arc hadbeen replaced by Thomas Edison's incandescent lamp.