An anemometer is used by meteorologists to measure wind speed.
  • Wind is the horizontal movement of air. The instrument used to measure wind speed is called an anemometer, which is an indicator that will spin in the wind. The anemometer rotates at the same speed as the wind. It gives a direct measure of the speed of the wind. Wind speed is measured by using the Beaufort Wind Scale which is a scale of 0-12 based on visual clues. 

    From: http://www.ciese.org/curriculum/weatherproj2/en/docs/anemometer.shtml#Instructions

Anemometers

  • An ANEMOMETER measures wind speed. The cups catch the wind, turning a dial attached to the instrument. The dial shows the wind speed. 

    From: weatherwizkids.com