1) Thermometer 
A cryometer is a thermometer used to measure very low temperatures of objects. There are many types of devices used as cryometers: ...
instrument for measuring low temperatures
• (n.) A thermometer for the measurement of low temperatures, esp. such an instrument containing alcohol or some other liquid of a lower freezing point than mercury.
A device for measuring very low temperatures. ... Origin: cryo-+ G. Metron, measure ... (05 Mar 2000) ... 
(kri-om´ә-tәr) a thermometer for measuring very low temperature.
Cry·om'e·ter noun [ Greek ... cold, frost + -meter .] (Physics) A thermometer for the measurement of low temperatures, esp. such an instrument containing alcohol or some other liquid of a lower freezing point than mercury. 
Type: Term Pronunciation: krī-om′ĕ-ter Definitions: 1. A device for measuring low temperatures.
[n] - a thermometer designed to measure low temperatures
cryometer A device for measuring very low temperatures.
noun a thermometer designed to measure low temperatures
a thermometer for measuring low temperatures.