voltmeter

noun Electricity.

1. a calibrated instrument for measuring the potential difference between two points.

noun

1. an instrument for measuring potential difference or electromotive force

n.

1882, from volt + meter (n.3).

1. An instrument used for measuring the difference in voltage between two points in an electric circuit. Voltmeters typically make use of an ammeter that measures current flow across a known resistance inside the voltmeter; direct-current voltages can then be determined by Ohm’s law. Digital voltmeters employ A/D converters to provide the numerical value of the voltage displayed. Compare ohmmeter.