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Related to minimum thermometer: Maximum thermometer
minimum thermometer[′min·ə·məm thər′mäm·əd·ər]
A thermometer that automatically registers the lowest temperature attained during an interval of time.
A thermometer that indicates the lowest temperature reached since the instrument was last set. It consists of alcohol or a similar medium in a glass tube. Within the liquid in the bore of the tube, there is a thin glass rod known as an index. When the liquid contracts as a result of a fall in the temperature, the index is pulled down. However, when the temperature rises, the alcohol flows around the index and rises in the tube, leaving the index at the lowest point to which the liquid surface descended. See maximum thermometer.