from
The Collaborative International Dictionary of English v.0.48
Pyrometer \Py*rom"e*ter\, n. [Pyro- + -meter: cf. F.
pyrom[`e]tre.]
1. (Physics) An instrument used for measuring the expansion
of solid bodies by heat.
[1913 Webster]
2. (Physics) An instrument for measuring degrees of heat
above those indicated by the mercurial thermometer.
[1913 Webster]
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.
[1913 Webster] Pyrometric