HEAT, n. [L. aestus, for haestus, or caestus.]1. Heat, as a cause of sensation, that is, the matter of heat, is considered to be a subtil fluid, contained in a greater or less degree in all bodies. In modern chimistry, it is called caloric. It expands all bodies in different proportions, and is the cause of fluidity and evaporation. A certain degree of it is also essential to animal and vegetable life. Heat is latent, when so combined with other matter as not to be perceptible. It is sensible, when it is evolved and perceptible.2. Heat, as a sensation, is the effect produced on the sentient organs of animals, by the passage of caloric, disengaged from surrounding bodies, to the organs. When we touch or approach a hot body, the caloric or heat passes from that body to our organs of feeling, and gives the sensation of heat. On the contrary, when we touch a cold body, the caloric passes from the hand to that body, and causes a sensation of cold.Note. This theory of heat seems not to be fully settled.3. Hot air; hot weather; as the heat of the tropical climates.4. Any accumulation or concentration of the matter of heat or caloric; as the heat of the body; the heat of a furnace; a red heat; a white heat; a welding heat.5. The state of being once heated or hot. Give the iron another heat.6. A violent action unintermitted; a single effort. Many causes are required for refreshment between the heats.7. A single effort in running; a course at a race. Hector won at the first heat.8. Redness of the face; flush.9. Animal excitement; violent action or agitation of the system. The body is all in a heat.
10. Utmost violence; rage; vehemence; as the heat of battle.
11. Violence; ardor; as the heat of party.
12. Agitation of mind; inflammation or excitement; exasperation; as the heat of passion.
13. Ardor; fervency; animation in thought or discourse. With all the strength and heat of eloquence.
HEAT, v.t. [L. odi, osus, for hodi, hosus; L aestus, for haestus, heat, tide; Gr. to burn, and the English haste and hoist are probably of the same family.]1. To make hot; to communicate heat to, or cause to be hot; as, to heat an oven or a furnace; to heat iron.2. To make feverish; as, to heat the blood.3. To warm with passion or desire; to excite; to rouse into action. A noble emulation heats your breast.4. To agitate the blood and spirits with action; to excite animal action.
HEAT, v.i. To grow warm or hot by fermentation, or extrication of latent heat. Green hay heats in a mow, and green corn in a bin.1. To grow warm or hot. The iron or the water heats slowly.
HEAT, for heated, is in popular use and pronounced het; but it is not elegant.