thermo-, therm-, thermi-, -thermia, -therm, -thermal, -thermic, -thermias, -thermies, -thermous, -thermy

(Greek: heat, heating, heater, hot, warm)

The term heat is employed in ordinary language in different senses. Some scientists distinguish four principal applications of the term:

  1. Sensation of heat.
  2. Temperature, or degree of hotness.
  3. Quantity of thermal energy.
  4. Radiant heat, or energy of radiation.

thermic sense, temperature sense
1. The network of sense organs and connecting pathways that allow differences in temperature changes.
2. The sense by which differences of temperature are distinguished by thermoreceptors or bodily sense receptors that respond to stimulations of heat and cold temperatures.
3. The capability of perceiving cold and warmth, and so being aware of the differences in the temperatures of external objects.
An electron which has been emitted from a heated body; such as, the hot cathode of an electron tube.
A reference to the emission of electrons as a result of heat.
thermionic electron
An electron emitted by heating a substance.
thermionic emission
1. The emission of electrons or ions by substances that are highly heated, the charged particles being called thermions.
2. The discharge of electrons or ions from a solid or liquid as a result of its thermal energy.
3. The release of electrons when a material is heated; for example, electron emission when the tungsten cathode filament of a radiographic tube is heated to incandescence (emission of light by an object as a result of its being heated to a high temperature) by means of its low-voltage heating circuit.
The study and applications of thermionic emissions, or charged particles, from heated surfaces.
thermite, thermit
A mixture of finely divided aluminum and oxide of iron or other metal, that produces on combustion (when ignited) a very high temperature (about 3,000°C); used in thermite processing, welding, and incendiary bombs.
thermoacidophile (s) (noun), thermoacidophiles (pl)
One of the archaebacteria that grows in hot sulfur springs at low pH: A thermoacidophile is an extremophilic microorganism that is thermophilic as well as acidophilic and can be located in vents on the seafloor or in other geothermal activity.
thermoaesthesia, thermoesthesia (s) (noun); thermoaesthesias; thermoesthesias (pl)
The body's ability to recognize and to respond to heat and cold; the sense of temperature: The body’s thermoaesthesia seems to be responsible for people's shivering or sweating depending on whether the temperatures are cold or hot during their activities.
thermoalgesia (s) (noun) (no pl)
Pain caused by a slight degree of heat: Heat pain, or thermoalgesia, can be caused by muscle spasms, perhaps originating by a person's body being overheated and needing electrolytes, in which it is important to stop the activity, rest in a cool and shady spot, and drink something nice, but nothing alcoholic!

As a fever indicates that the body is fighting infection, pain has its purpose in reporting injury or internal problems. Unfortunately, pain is not a reliable indicator, and it is of limited help to a physician in forming an accurate diagnosis.

The perception of a pain’s very source may be incorrect. The tooth that one points out as the one that hurts may not be the one that’s abscessed.

That pain in a person’s arm may not be caused by a strain or injury to that area, but it could be the result of a problem in his/her heart or other organ.

These are examples of a phenomenon known as "referred pain".

—Neil McAleer in The Body Almanac;
Doubleday & Company, Inc., Garden City, New York, 1985; page 92.
In engineering, an ammeter that employs a thermocouple to measure radio-frequency current.
thermoanalgesia (s) (noun) (no pl)
Insensibility to heat or to temperature changes: In medical school, Lynn learned that thermoanalgesia applied to the absence of pain when a hot stimulus was applied to a person.
1. In analytical chemistry, any test using heat for the analysis of thermodynamic or physical properties of materials, including distillation, calorimetry, and boiling and freezing point determinations.
2. Used in metallurgy, specifically, a test used to determine metal transformations based on the temperatures at which thermal arrests occur.
thermoanesthesia, thermoanaesthesia (British) (noun); thermoanesthesias; thermoanaesthesias (pl)
Loss of the normal sense of temperature, or the loss of one's ability to differentiate between what is hot or of any degree of coldness: After his severe illness, Thomas appeared to experience thermoanesthesia and couldn't tell whether something was hot or cold, such as when he washed his hands after turning on the faucet with very hot water.
A difference in temperature noted between corresponding parts of the body on the two sides as seen in unilateral lesions of sympathetic pathways.

Quiz You can find self-scoring quizzes over many of the words in this subject area by going to this Thermo- Vocabulary Quizzes page.

Related "heat, hot" word units: ferv-; pyreto-.

Related "bubble" word unit: ebulli-.