metrograph

== English == === Etymology === From metro- +‎ -graph. === Noun === metrograph (plural metrographs) An instrument attached to a locomotive for recording its speed and the number and duration of its stops. A device used to measure the flow and velocity of liquids. Any of various devices that continuously record several meteorological phenomena; a radiosonde or one of its precursors. A device that uses reflection holograms to accurately measure three-dimensional objects, used primarily in orthodontics. === Anagrams === tremograph