Therefore, "thermo-" indicates a relationship to heat or temperature.
Here are some examples of words with the prefix "thermo-":
* Thermometer: An instrument for measuring temperature.
* Thermodynamics: The branch of physics that deals with heat and its relation to other forms of energy.
* Thermostat: A device that regulates temperature.
* Thermos: A container designed to keep hot liquids hot and cold liquids cold.
* Thermal: Relating to heat.
So, whenever you see "thermo-" in a word, it's a clue that the word relates to heat or temperature in some way.