The gauge or meter used to measure windspeed is known as anemometer. An anemometer can also be used to measure the airspeed, airflow, or air velocity both in the outdoor environment and in the indoor environment such as in ventilation ducts. They are also important instruments for meteorologists that study weather patterns.
Wind speed instruments, depending on the model, may also come with additional features such as the ability to measure wind and ambient temperature along with air pressure and may come with data logging capabilities.