速度計
an instrument used to measure the rate of flow, called a current meter
an apparatus used to measure speed, called speedometer
an instrument used to measure force or power
a hydrometer whose degrees are calibrated in accordance with a Baume scale, called Baume hydrometer
an instrument used as a gauge
an instrument used to measure angles
an instrument used for navigating
a tachometer that produces a graphical record of its readings