[1] : The Collaborative International Dictionary of English v.0.48

heat \heat\ h=et, n. oe. hete, haete, as. h=aetu,
   h=aeto, fr. h=at hot; akin to ohg. heizi heat, dan. hede,
   sw. hetta. see hot.
   1. a force in nature which is recognized in various effects,
      but especially in the phenomena of fusion and evaporation,
      and which, as manifested in fire, the sun's rays,
      mechanical action, chemical combination, etc., becomes
      directly known to us through the sense of feeling. in its
      nature heat is a mode of motion, being in general a form
      of molecular disturbance or vibration. it was formerly
      supposed to be a subtile, imponderable fluid, to which was
      given the name caloric.
      1913 webster

   note: as affecting the human body, heat produces different
         sensations, which are called by different names, as
         heat or sensible heat, warmth, cold, etc., according to
         its degree or amount relatively to the normal
         temperature of the body.
         1913 webster

   2. the sensation caused by the force or influence of heat
      when excessive, or above that which is normal to the human
      body; the bodily feeling experienced on exposure to fire,
      the sun's rays, etc.; the reverse of cold.
      1913 webster

   3. high temperature, as distinguished from low temperature,
      or cold; as, the heat of summer and the cold of winter;
      heat of the skin or body in fever, etc.
      1913 webster

            else how had the world . . .
            avoided pinching cold and scorching heat --milton.
      1913 webster

   4. indication of high temperature; appearance, condition, or
      color of a body, as indicating its temperature; redness;
      high color; flush; degree of temperature to which
      something is heated, as indicated by appearance,
      condition, or otherwise.
      1913 webster

            it has raised . . . heats in their faces. --addison.
      1913 webster

            the heats smiths take of their iron are a blood-red
            heat, a white-flame heat, and a sparkling or welding
            heat.                                 --moxon.
      1913 webster

   5. a single complete operation of heating, as at a forge or
      in a furnace; as, to make a horseshoe in a certain number
      of heats.
      1913 webster

   6. a violent action unintermitted; a single effort; a single
      course in a race that consists of two or more courses; as,
      he won two heats out of three.
      1913 webster

            many causes . . . for refreshment betwixt the heats.
                                                  --dryden.
      1913 webster

            he struck off at one heat the matchless tale of
            "tam o' shanter."                     --j. c.
                                                  shairp.
      1913 webster

   7. utmost violence; rage; vehemence; as, the heat of battle
      or party. "the heat of their division." --shak.
      1913 webster

   8. agitation of mind; inflammation or excitement;
      exasperation. "the heat and hurry of his rage." --south.
      1913 webster

   9. animation, as in discourse; ardor; fervency; as, in the
      heat of argument.
      1913 webster

            with all the strength and heat of eloquence.
                                                  --addison.
      1913 webster

   10. zool. sexual excitement in animals; readiness for
       sexual activity; estrus or rut.
       1913 webster +pjc

   11. fermentation.
       1913 webster

   12. strong psychological pressure, as in a police
       investigation; as, when they turned up the heat, he took
       it on the lam. slang
       pjc

   animal heat, blood heat, capacity for heat, etc. see
      under animal, blood, etc.

   atomic heat chem., the product obtained by multiplying
      the atomic weight of any element by its specific heat. the
      atomic heat of all solid elements is nearly a constant,
      the mean value being 6.4.

   dynamical theory of heat, that theory of heat which assumes
      it to be, not a peculiar kind of matter, but a peculiar
      motion of the ultimate particles of matter.

   heat engine, any apparatus by which a heated substance, as
      a heated fluid, is made to perform work by giving motion
      to mechanism, as a hot-air engine, or a steam engine.

   heat producers. physiol. see under food.

   heat rays, a term formerly applied to the rays near the red
      end of the spectrum, whether within or beyond the visible
      spectrum.

   heat weight mech., the product of any quantity of heat by
      the mechanical equivalent of heat divided by the absolute
      temperature; -- called also thermodynamic function, and
      entropy.

   mechanical equivalent of heat. see under equivalent.

   specific heat of a substance at any temperature, the
      number of units of heat required to raise the temperature
      of a unit mass of the substance at that temperature one
      degree.

   unit of heat, the quantity of heat required to raise, by
      one degree, the temperature of a unit mass of water,
      initially at a certain standard temperature. the
      temperature usually employed is that of 0deg centigrade,
      or 32deg fahrenheit.
      1913 webster
see also:
hot caloric cold animal heat blood heat capacity for heat 
animal blood atomic heat dynamical theory of heat heat engine 
heat producers food heat rays heat weight thermodynamic function 
entropy mechanical equivalent of heat equivalent specific heat of a substance at any temperature unit of heat 

Heat >> H Words
Heat, definition of term: Heat
heat_pag1.html

Heat Pump >> H Words
Heat Pump, definition of term: Heat Pump
heat+pump_pag1.html

Heat Exhaustion >> H Words
Heat Exhaustion, definition of term: Heat Exhaustion
heat+exhaustion_pag1.html

Heat Exchanger >> H Words
Heat Exchanger, definition of term: Heat Exchanger
heat+exchanger_pag1.html

Heat Energy >> H Words
Heat Energy, definition of term: Heat Energy
heat+energy_pag1.html

Gamma Rays >> G Words
Gamma Rays, definition of term: Gamma Rays
gamma+rays_pag1.html

Heat Of Fusion >> H Words
Heat Of Fusion, definition of term: Heat Of Fusion
heat+of+fusion_pag1.html

Heat Of Vaporiz >> H Words
Heat Of Vaporiz, definition of term: Heat Of Vaporiz
heat+of+vaporiz_pag1.html