tachometer

Definitions

Aviation

Cars & Driving

  • noun an instrument in the instrument panel, electronically operated by the ignition system, which indicates engine rpm with an analogue or digital read-out; red areas indicate dangerous engine operating speeds.

Construction

  • A device for measuring rotation speed. Usually refers to revolutions per minute (RPM) of a revolving shaft.

Electronics

  • A device or instrument which measures and indicates angular velocity. When graduated in revolutions per minute, also called RPM meter. Its abbreviation is tach.
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