pīˈräməd.ə(r) noun
Etymology: International Scientific Vocabulary pyr- + -meter
: an instrument for measuring temperatures (as beyond the range of thermometers) usually by the increase of electric resistance in a metal when heated, by the generation of electric current by a thermocouple when acted upon by direct heat or focused radiation, or by the increase in intensity of light radiated by an incandescent body as its temperature increases — see optical pyrometer , radiation pyrometer