n. [ OE. hete, hæte, AS. h&aemacr_;tu, h&aemacr_;to, fr. hāt 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 ]

☞ 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 0° Centigrade, or 32° Fahrenheit. [ 1913 Webster ]

imp. & p. p. of Heat. Heated; as, the iron though heat red-hot. [ Obs. or Archaic ] Shak. [ 1913 Webster ]

v. t. [ imp. & p. p. Heated; p. pr. & vb. n. Heating. ] [ OE. heten, AS. h&aemacr_;tan, fr. hāt hot. See Hot. ] 1. To make hot; to communicate heat to, or cause to grow warm; as, to heat an oven or furnace, an iron, or the like. [ 1913 Webster ]

Heat me these irons hot. Shak. [ 1913 Webster ]

2. To excite or make hot by action or emotion; to make feverish. [ 1913 Webster ]

Pray, walk softly; do not heat your blood. Shak. [ 1913 Webster ]

3. To excite ardor in; to rouse to action; to excite to excess; to inflame, as the passions. [ 1913 Webster ]

A noble emulation heats your breast. Dryden. [ 1913 Webster ]

v. i. 1. To grow warm or hot by the action of fire or friction, etc., or the communication of heat; as, the iron or the water heats slowly. [ 1913 Webster ]

2. To grow warm or hot by fermentation, or the development of heat by chemical action; as, green hay heats in a mow, and manure in the dunghill. [ 1913 Webster ]

adj. 1. characterized by great warmth and intensity of feeling; as, a heated argument. Opposite of dispassionate, passionless. [ wns=1 ]
Syn. -- ardent, fervent, fervid, fiery, hot, impassioned, perfervid, torrid. [ WordNet 1.5 ]

2. supplied with a mechanism for heating; -- of structures or devices; as, a heated fishing cabin. Opposite of unheated. [ wns=2 ] [ WordNet 1.5 +PJC ]

n. 1. One who, or that which, heats. [ 1913 Webster ]

2. Any contrivance or implement, as a furnace, stove, or other heated body or vessel, etc., used to impart heat to something, or to contain something to be heated. [ 1913 Webster ]

3. A pistol or other carryable firearm; as, gunmen with their heaters bulging in their pockets. [ slang ] [ PJC ]

Feed heater. See under Feed. [ 1913 Webster ]

n. [ OE. heth waste land, the plant heath, AS. h&aemacr_;ð; akin to D. & G. heide, Icel. heiðr waste land, Dan. hede, Sw. hed, Goth. haiþi field, L. bucetum a cow pasture; cf. W. coed a wood, Skr. kshētra field. √20. ] 1. (Bot.) (a) A low shrub (Erica vulgaris or Calluna vulgaris), with minute evergreen leaves, and handsome clusters of pink flowers. It is used in Great Britain for brooms, thatch, beds for the poor, and for heating ovens. It is also called heather, and ling. (b) Also, any species of the genus Erica, of which several are European, and many more are South African, some of great beauty. See Illust. of Heather. [ 1913 Webster ]

2. A place overgrown with heath; any cheerless tract of country overgrown with shrubs or coarse herbage. [ 1913 Webster ]

Their stately growth, though bare,
Stands on the blasted heath. Milton [ 1913 Webster ]

Heath cock (Zool.), the blackcock. See Heath grouse (below). --
Heath grass (Bot.), a kind of perennial grass, of the genus Triodia (Triodia decumbens), growing on dry heaths. --
Heath grouse, or
Heath game (Zool.), a European grouse (Tetrao tetrix), which inhabits heaths; -- called also black game, black grouse, heath poult, heath fowl, moor fowl. The male is called heath cock, and blackcock; the female, heath hen, and gray hen. --
Heath hen. (Zool.) See Heath grouse (above). --
Heath pea (Bot.), a species of bitter vetch (Lathyrus macrorhizus), the tubers of which are eaten, and in Scotland are used to flavor whisky. --
Heath throstle (Zool.), a European thrush which frequents heaths; the ring ouzel. [ 1913 Webster ]

a. Clad or crowned with heath. [ 1913 Webster ]

n.; pl. Heathens r collectively Heathen. [ OE. hethen, AS. h&aemacr_;ðen, prop. an adj. fr. h&aemacr_;ð heath, and orig., therefore, one who lives in the country or on the heaths and in the woods (cf. pagan, fr. pagus village); akin to OS. hēðin, adj., D. heiden a heathen, G. heide, OHG. heidan, Icel. heiðinn, adj., Sw. heden, Goth. haiþnō, n. fem. See Heath, and cf. Hoiden. ] 1. An individual of the pagan or unbelieving nations, or those which worship idols and do not acknowledge the true God; a pagan; an idolater. [ 1913 Webster ]

2. An irreligious person. [ 1913 Webster ]

If it is no more than a moral discourse, he may preach it and they may hear it, and yet both continue unconverted heathens. V. Knox. [ 1913 Webster ]

The heathen, as the term is used in the Scriptures, all people except the Jews; now used of all people except Christians, Jews, and Muslims. [ 1913 Webster ]

Ask of me, and I shall give thee the heathen for thine inheritance. Ps. ii. 8.

Syn. -- Pagan; gentile. See Pagan. [ 1913 Webster ]

a. 1. Gentile; pagan; as, a heathen author. “The heathen philosopher.” “All in gold, like heathen gods.” Shak. [ 1913 Webster ]

2. Barbarous; unenlightened; heathenish. [ 1913 Webster ]

3. Irreligious; scoffing. [ 1913 Webster ]