PSYCHROMETER

[psy.chrom.e.ter] n [ISV] (1838): a hygrometer consisting essentially of two similar thermometers with the bulb of one being kept wet so that the cooling that results from evaporation makes it register a lower temperature than the dry one and with the difference between the readings constituting a measure of the dryness of the atmosphere -- psy.chro.met.ric adj -- psy.chrom.e.try n