THERMOGRAPH

n. instrument for recording temperature variations (Meteorology)

A thermograph is a recording thermometer. Usually configured with a pen that records temperature on a revolving cylinder. The pen is at the end of a lever that is controlled by a bi-metal strip of temperature-sensitive metal which bends as the temperature changes.
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Noun
1. medical instrument that uses an infrared camera to reveal temperature variations on the surface of the body
(hypernym) medical instrument
2. a thermometer that records temperature variations on a graph as a function of time
(synonym) thermometrograph
(hypernym) thermometer

n. thermograph, instrument for recording variations of temperature (Meteorology)

(n.)
An instrument for automatically recording indications of the variation of temperature.