Akademik

a meter fixed to a vehicle that measures and displays its speed

1. or speed gage

a. : speed counter

b. : tachometer

2. : a device (as a display of canvas cones, a flashing or steady display of lights, or a display of flags) for showing the speed of a ship to other vessels in a formation

an instrument for counting the number of revolutions of a gasoline engine. Also called speed counter.

[1855-60]

speed counter or speed indicator,

any one of various devices for indicating the speed of an engine, such as a tachometer or speedometer.