The Collaborative International Dictionary of English v.0.48:
Horse \Horse\ (h[^o]rs), n. [AS. hors; akin to OS. hros, D. &
OHG. ros, G. ross, Icel. hross; and perh. to L. currere to
run, E. course, current Cf. Walrus.]
1. (Zool.) A hoofed quadruped of the genus Equus;
especially, the domestic horse (Equus caballus), which
was domesticated in Egypt and Asia at a very early period.
It has six broad molars, on each side of each jaw, with
six incisors, and two canine teeth, both above and below.
The mares usually have the canine teeth rudimentary or
wanting. The horse differs from the true asses, in having
a long, flowing mane, and the tail bushy to the base.
Unlike the asses it has callosities, or chestnuts, on all
its legs. The horse excels in strength, speed, docility,
courage, and nobleness of character, and is used for
drawing, carrying, bearing a rider, and like purposes.
Note: Many varieties, differing in form, size, color, gait,
speed, etc., are known, but all are believed to have
been derived from the same original species. It is
supposed to have been a native of the plains of Central
Asia, but the wild species from which it was derived is
not certainly known. The feral horses of America are
domestic horses that have run wild; and it is probably
true that most of those of Asia have a similar origin.
Some of the true wild Asiatic horses do, however,
approach the domestic horse in several characteristics.
Several species of fossil (Equus) are known from the
later Tertiary formations of Europe and America. The
fossil species of other genera of the family
Equid[ae] are also often called horses, in general
2. The male of the genus Equus, in distinction from the
female or male; usually, a castrated male.
3. Mounted soldiery; cavalry; -- used without the plural
termination; as, a regiment of horse; -- distinguished
The armies were appointed, consisting of twenty-five
thousand horse and foot. --Bacon.
4. A frame with legs, used to support something; as, a
clotheshorse, a sawhorse, etc.
5. A frame of timber, shaped like a horse, on which soldiers
were made to ride for punishment.
6. Anything, actual or figurative, on which one rides as on a
horse; a hobby.
7. (Mining) A mass of earthy matter, or rock of the same
character as the wall rock, occurring in the course of a
vein, as of coal or ore; hence, to take horse -- said of a
vein -- is to divide into branches for a distance.
(a) See Footrope, a.
(b) A breastband for a leadsman.
(c) An iron bar for a sheet traveler to slide upon.
(d) A jackstay. --W. C. Russell. --Totten.
9. (Student Slang)
(a) A translation or other illegitimate aid in study or
examination; -- called also trot, pony, Dobbin.
(b) Horseplay; tomfoolery.
[Webster 1913 Suppl.]
10. heroin. [slang]
11. horsepower. [Colloq. contraction]
Note: Horse is much used adjectively and in composition to
signify of, or having to do with, a horse or horses,
like a horse, etc.; as, horse collar, horse dealer or
horse?dealer, horsehoe, horse jockey; and hence, often
in the sense of strong, loud, coarse, etc.; as,
horselaugh, horse nettle or horse-nettle, horseplay,
horse ant, etc.
Black horse, Blood horse, etc. See under Black, etc.
Horse aloes, caballine aloes.
Horse ant (Zool.), a large ant (Formica rufa); -- called
also horse emmet.
Horse artillery, that portion of the artillery in which the
cannoneers are mounted, and which usually serves with the
cavalry; flying artillery.
Horse balm (Bot.), a strong-scented labiate plant
(Collinsonia Canadensis), having large leaves and
Horse bean (Bot.), a variety of the English or Windsor bean
(Faba vulgaris), grown for feeding horses.
Horse boat, a boat for conveying horses and cattle, or a
boat propelled by horses.
Horse bot. (Zool.) See Botfly, and Bots.
Horse box, a railroad car for transporting valuable horses,
as hunters. [Eng.]
Horse breaker or Horse trainer, one employed in subduing
or training horses for use.
(a) A railroad car drawn by horses. See under Car.
(b) A car fitted for transporting horses.
Horse cassia (Bot.), a leguminous plant (Cassia
Javanica), bearing long pods, which contain a black,
catharic pulp, much used in the East Indies as a horse
Horse cloth, a cloth to cover a horse.
Horse conch (Zool.), a large, spiral, marine shell of the
genus Triton. See Triton.
(a) One that runs horses, or keeps horses for racing.
(b) A dealer in horses. [Obs.] --Wiseman.
Horse crab (Zool.), the Limulus; -- called also
horsefoot, horsehoe crab, and king crab.
Horse crevall['e] (Zool.), the cavally.
Horse emmet (Zool.), the horse ant.
Horse finch (Zool.), the chaffinch. [Prov. Eng.]
Horse gentian (Bot.), fever root.
Horse iron (Naut.), a large calking iron.
Horse latitudes, a space in the North Atlantic famous for
calms and baffling winds, being between the westerly winds
of higher latitudes and the trade winds. --Ham. Nav.
Horse mackrel. (Zool.)
(a) The common tunny (Orcynus thunnus), found on the
Atlantic coast of Europe and America, and in the
(b) The bluefish (Pomatomus saltatrix).
(c) The scad.
(d) The name is locally applied to various other fishes,
as the California hake, the black candlefish, the
jurel, the bluefish, etc.
Horse marine (Naut.), an awkward, lubbery person; one of a
mythical body of marine cavalry. [Slang]
Horse mussel (Zool.), a large, marine mussel (Modiola
modiolus), found on the northern shores of Europe and
Horse nettle (Bot.), a coarse, prickly, American herb, the
Horse parsley. (Bot.) See Alexanders.
Horse purslain (Bot.), a coarse fleshy weed of tropical
America (Trianthema monogymnum).
Horse race, a race by horses; a match of horses in running
Horse racing, the practice of racing with horses.
Horse railroad, a railroad on which the cars are drawn by
horses; -- in England, and sometimes in the United States,
called a tramway.
Horse run (Civil Engin.), a device for drawing loaded
wheelbarrows up an inclined plane by horse power.
Horse sense, strong common sense. [Colloq. U.S.]
Horse soldier, a cavalryman.
Horse sponge (Zool.), a large, coarse, commercial sponge
Horse stinger (Zool.), a large dragon fly. [Prov. Eng.]
Horse sugar (Bot.), a shrub of the southern part of the
United States (Symplocos tinctoria), whose leaves are
sweet, and good for fodder.
Horse tick (Zool.), a winged, dipterous insect (Hippobosca
equina), which troubles horses by biting them, and
sucking their blood; -- called also horsefly, horse
louse, and forest fly.
Horse vetch (Bot.), a plant of the genus Hippocrepis
(Hippocrepis comosa), cultivated for the beauty of its
flowers; -- called also horsehoe vetch, from the
peculiar shape of its pods.
Iron horse, a locomotive. [Colloq.]
Salt horse, the sailor's name for salt beef.
To look a gift horse in the mouth, to examine the mouth of
a horse which has been received as a gift, in order to
ascertain his age; -- hence, to accept favors in a
critical and thankless spirit. --Lowell.
To take horse.
(a) To set out on horseback. --Macaulay.
(b) To be covered, as a mare.
(c) See definition 7 (above).