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.

thermocline
1. In geophysics, a layer in a body of water at which the rate of temperature decreases when depth is at a maximum; such as, a thin layer of water at the depth range of 300-800 meters in the tropical and subtropical basins, between the deep abyssal waters and the surface mixed layer.
2. A horizonal temphorizontal temperature discontinuity layer in a lake in which the temperature falls by at least 1°C per meter depth.
3. A boundary layer in the sea in which temperature changes sharply with depth.
thermocoagulation
1. The process of converting tissue into a gel by heat.
2. Coagulation of tissue by the action of high-frequency currents; used in removal of growths and also used to produce stereotactic lesions in the brain.
3. Destruction and removal of tissue by coagulation utilizing high-frequency electric current.
thermocompression
In mechanics, any process involving both heat and pressure.
thermocurrent (s) (noun), thermocurrents (pl)
Electricity that is developed or set in motion by heat: Some thermocurrents are produced by differences of temperatures that exist between the connections which produce electricity at various speeds.
thermocyclogenesis
In meteorology, a cyclogenetic model in which a disturbance initiated in the stratosphere is reflected in the development of a disturbance in the lower troposphere.
thermodiffusion (s) (noun), thermodiffusions (pl)
1. Diffusion of fluids, either gaseous or liquid, as influenced by the temperature of the fluid.
2. A process in which temperature differentiation within a fluid mixture causes one constituent to flow differently than the mixture as a whole.
thermodilution
1. Diffusion of fluids, either gaseous or liquid, as influenced by the temperature of the fluid.
2. A method of measuring ventricular blood volume and cardiac output in which a cold or cool indicator; such as, a saline solution or distilled water, is injected and sampled by a thermistor (a kind of thermometer for measuring very small changes in temperature).
thermoduric
1. Resistant to the effects of exposure to high temperature; used especially with reference to microorganisms.
2. Capable of withstanding, or able to tolerate, high temperatures.
3. The ability to resist heat.
4. Resistant to the decomposing effects of heat.
thermodynamic
1. In physics, a description of supplying, using, or accepting energy.
2. Of or relating to thermodynamics.
thermodynamics, thermodynamical, thermodynamically
1. The branch of physicochemical science concerned with heat and energy and their conversions one into the other involving mechanical work.
2. The branch science which is concerned with the study of energy and with the relationship of heat transfer and work to other forms of energy.
3. The study of the flow of heat.
4. A branch of science dealing with heat, energy, and the interconversion of these, and with related problems.

Thermodynamics is the physical science that accounts for the transformation of thermal energy into mechanical energy and its equivalent forms in which temperature is a significant factor; such as, electricity and self-organization of complex systems.

thermoeconomics
The integration of thermodynamics and economics in order to make technical systems efficient, by finding the most economical solutions within the limits of what is technically possible.
thermoelasticity
1. A topic in thermodynamics which deals with the compressibility of substances.
2. A condition of elasticity exhibited by a normally rigid material due to an increase in temperature.
thermoelectric cooler, thermoelectric cooling
An electronic heat pump used to produce cooling with a thermoelectric effect, consisting of a thermocouple with its "cold" end in the chamber to be cooled and its "hot" end in an outside heat sink.
thermoelectric, thermoelectrically
Involving or produced by thermoelectricity; that is, electrical phenomena occurring in conjunction with a flow of heat
thermoelectricity
1. An electrical current generated in a thermopile.
2. Electricity generated by heat.
3. Electricity produced by the direct action of heat or the direct conversion of heat into electricity; such as, in a thermocouple.

When two metals are placed in electric contact, electrons flow out of the one in which the electrons are less bound and into the other.

The binding is measured by the location of the so-called Fermi level of electrons in the metal; the higher the level, the lower is the binding.

The Fermi level represents the demarcation in energy within the conduction band of a metal between the energy levels occupied by electrons and those that are unoccupied. It is important in determining the electrical and thermal properties of solids.

The Fermi level is the measure of the energy of the least tightly held electrons within a solid; named for Enrico Fermi, Italian-born American physicist who first proposed it and who was one of the chief architects of the nuclear age.

He developed the mathematical statistics required to clarify a large class of subatomic phenomena, explored nuclear transformations caused by neutrons, and directed the first controlled chain reaction involving nuclear fission.

—Compiled from "Thermoelectricity", Encyclopædia Britannica; 2010;
Encyclopædia Britannica Online; June 6, 2010.

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-.