(meteorology) An instrument that measures the humidity of the air or other gases, especially the relative humidity.

plural of hygrometer

plural of absorption hygrometer

(meteorology) An instrument utilizing organic material to measure the atmospheric moisture level.

(meteorology) A hygrometer consisting of two thermometers, the bulb of one of which is kept wet and shows a lower temperature; the relative humidity is obtained from the two temperatures using tables.

plural of wet-and-dry-bulb hygrometer