'Pyroscope' definitions:

Definition of 'pyroscope'

noun

A pyrometer that uses the color of the light emitted by a hot object [syn: optical pyrometer, pyroscope]

From: GCIDE

Pyroscope \Pyr"o*scope\, n. [Pyro- + -scope: cf. F. pyroscope.] (Physics) An instrument for measuring the intensity of heat radiating from a fire, or the cooling influence of bodies. It is a differential thermometer, having one bulb coated with gold or silver leaf. [R.] [1913 Webster]