It is derived from the Greek word "therme" meaning "heat".
Here are some examples of words with the suffix "-thermia":
* Hyperthermia: Abnormally high body temperature.
* Hypothermia: Abnormally low body temperature.
* Normothermia: Normal body temperature.
* Febrile: Having a fever, characterized by a raised body temperature.
So, when you see "-thermia" in a word, you can usually infer that it relates to the state or condition of body temperature.