noun
minimum thermometer
A thermometer that records the lowest temperature reached over a period, used in meteorology and cold-chain monitoring.
気象観測では、最低温度計を使ってその日の最低気温を記録します。
In meteorological observation, a minimum thermometer is used to record the day's lowest temperature.
Compound of 最低 (lowest) + 温度 (temperature) + 計 (meter).