tachimetro
- A tachymeter is an instrument used to measure speed, typically the speed of a vehicle, or to measure the rate of something. It is often found as a scale on the bezel of a chronograph watch, allowing the user to compute speed based on travel time or measure distance based on speed. nounThe tachimetro on his watch allowed him to calculate the speed of the car over a measured distance.She used the tachimetro to determine how fast the runner was going during the race.