Pyrometer
Pronunciation : Py*rom"e*ter
Part of Speech : n.
Etymology : [Pyro- + -meter: cf. F. pyrom?tre.]
Definition : 1. (Physics)
Defn: An instrument used for measuring the expansion of solid bodies by heat.
2. (Physics)
Defn: An instrument for measuring degrees of heat above those indicated by the mercurial thermometer.
Note: It is usually constructed so as to register the change which the heat to be measured produces in the length of some expansible substance, as a metallic rod, or in the intensity of a thermo- electric current.
Source : Webster's Unabridged Dictionary, 1913