hygrometer
/haɪˈɡɹɒmɪtə(ɹ)/ noun
Forms hygrometers hygrometre
- noun (meteorology) An instrument that measures the humidity of the air or other gases, especially the relative humidity.
Etymology
From French hygromètre, from hygro- + -meter.
Webster’s 1913
- noun An instrument for measuring the degree of moisture of the atmosphere. Daniell's hygrometer, a form of hygrometer consisting of a bent glass tube terminating in two bulbs, the one covered with muslin, the other of black glass, and containing ether and a thermometer. Ether being poured on the muslin, the black ball, cooled by the evaporation of the ether within, is soon covered with dew; at this moment, the inclosed thermometer gives the dew-point, and this, compared with the reading of one in the air, determines the humidity.
Etymology [Gr. -meter: cf. F. hygromètre.]
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “hygrometer”, CC BY-SA 4.0. Details