Source : Webster's Revised Unabridged Dictionary (1913)

Telethermometer \Tel`e*ther*mom"e*ter\, n. [Gr. ? far off + E.
   thermometer.] (Physics)
   An apparatus for determining the temperature of a distant
   point, as by a thermoelectric circuit or otherwise.

Source : WordNet®

telethermometer
     n : a thermometer that registers the temperature at some distant
         point