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.

electrothermal ammeter, thermoammeter, thermocouple ammeter
An ammeter (device for measuring an electric current in amperes) that is actuated by the voltage generated in a thermocouple through which it receives the current to be measured.

It is used primarily for measuring radio-frequency currents.

electrothermal energy conversion
1. A process in which electrical energy is directly converted into heat energy.
2. The direct conversion of electric energy into heat energy, as in an electric heater.
electrothermal expansion element
An actuating element consisting of a wire strip or other shape and having a high coefficient of thermal expansion.
electrothermal instrument
An apparatus which depends for its operation on the heating effect of an electric current.
electrothermal process
1. A process in which an electric current is used to produce heat.
2. Used to generate higher temperatures than can be produced by combustion processes.
3. Any process that uses an electric current to generate heat, utilizing resistance, arcs, or induction.

It is used to achieve temperatures higher than those which can be obtained by combustion methods.

electrothermal propulsion
1. A type of rocket propulsion in which the propellant is heated electrically; such as, an electric arc that is used to heat hydrogen gas in an arc-jet engine.
2. The propulsion of spacecraft by using an electric arc or other electric heater to bring hydrogen gas or other propellant to the high temperature required for maximum thrust; for example, an arc-jet engine.
3. Vehicular propulsion which involves electrical heating to raise the energy level of the propellant.

In contrast, chemical rockets use the chemical energy of one or more propellants to heat and to accelerate the decomposition products (monopropellants) or combustion products (bipropellants) for thrusting purposes.

In both instances, the high-energy propellant gases are exhausted through a nozzle where they are accelerated to a high velocity, and thrust is produced by reaction.

electrothermal recorder
A recorder in which heat produces an image on the recording medium in response to the received signals.
electrothermal recording
1. In facsimile (fax) or an instrument that transmits and reproduces documents with digitized signals which are sent over telephone lines, a technique in which an image is produced on a recording medium by heat generated by electronic signals.
2. A type of electrochemical recording, used in facsimile equipment, in which the chemical change is produced principally by signal-controlled thermal action.
electrothermal voltmeter
1. An electrothermal ammeter (instrument for measuring an electric current in amperes or basic units of electric current) employing a series resistor as a multiplier, and so measuring voltage instead of current.
2. An instrument which measures voltage and operates as an electrothermal ammeter, using a series resistor as a multiplier.
electrothermic
A reference to heat that is produced by electricity.
electrothermic instrument
An instrument that depends for its operation on the healing effect of a current.

Examples include the thermocouple, bolometric (a tool that detects and measures small amounts of thermal radiation), hot-wire, and hot-strip instruments.

electrothermics
A branch of science concerned with the direct transformation of electric energy into heat.
electrothermotherapy
The therapeutic heating or treatment of bodily tissues produced by the passage of electric currents through them.
electrothermy
The generation of heat with electricity to apply to the body surface to relieve pain.
endotherm
A warm-blooded animal; such as, an organism that maintains its body temperature by producing heat within the body.

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-.