a type of hygrometer consisting of two thermometers, one of which has a dry bulb and the other a bulb that is kept moist and ventilated. The difference between the readings of the thermometers gives an indication of atmospheric humidity
Also called: wet-and-dry-bulb thermometer
psychrometer in American English
(saɪˈkrɑmətər)
noun
an instrument with wet- and dry-bulb thermometers, for measuring moisture in the air