(Horde) n. [F. horde fr. Turk. ordu, ordi, camp; of Tartar origin.] A wandering troop or gang; especially,
a clan or tribe of a nomadic people migrating from place to place for the sake of pasturage, plunder,
etc.; a predatory multitude. Thomson.
(Hor*de"ic) a. [L. hordeum barley.] (Chem.) Pertaining to, or derived from, barley; as, hordeic
acid, an acid identical or isomeric with lauric acid.
(Hor"de*in) n. [L. hordeum barley.] (Chem.) A peculiar starchy matter contained in barley. It
is a complex mixture. [R.]
(||Hor*de"o*lum) n. [NL., fr. L. hordeolus, dim. of hordeum barley.] (Med.) A small tumor
upon the eyelid, resembling a grain of barley; a sty.
(Hor"dock`) n. An unidentified plant mentioned by Shakespeare, perhaps equivalent to burdock.
(Hore) a. Hoar. [Obs.] Chaucer.
Fetid horehound, or Black horehound, a disagreeable plant resembling horehound Water horehound,
a species of the genus Lycopus, resembling mint, but not aromatic.
(Hore"hound`) n. [OE. horehune, AS. harhune; har hoar, gray + hune horehound; cf. L.
cunila a species of organum, Gr. Skr. kny to smell.] (Bot.) A plant of the genus Marrubium which
has a bitter taste, and is a weak tonic, used as a household remedy for colds, coughing, etc. [Written
(Ho*ri"zon) n. [F., fr. L. horizon, fr. Gr. (sc. ) the bounding line, horizon, fr. to bound, fr. boundary,
1. The circle which bounds that part of the earth's surface visible to a spectator from a given point; the
apparent junction of the earth and sky.
And when the morning sun shall raise his carShak.
Above the border of this horizon.
All the horizon roundMilton.
Invested with bright rays.
2. (Astron.) (a) A plane passing through the eye of the spectator and at right angles to the vertical
at a given place; a plane tangent to the earth's surface at that place; called distinctively the sensible
horizon. (b) A plane parallel to the sensible horizon of a place, and passing through the earth's center;
called also rational or celestial horizon. (c) (Naut.) The unbroken line separating sky and water, as
seen by an eye at a given elevation, no land being visible.
3. (Geol.) The epoch or time during which a deposit was made.
The strata all over the earth, which were formed at the same time, are said to belong to the same geological
4. (Painting) The chief horizontal line in a picture of any sort, which determines in the picture the height
of the eye of the spectator; in an extended landscape, the representation of the natural horizon corresponds
with this line.
Apparent horizon. See under Apparent. Artificial horizon, a level mirror, as the surface of mercury
in a shallow vessel, or a plane reflector adjusted to the true level artificially; used chiefly with the sextant
for observing the double altitude of a celestial body. Celestial horizon. (Astron.) See def. 2, above.
Dip of the horizon (Astron.), the vertical angle between the sensible horizon and a line to the
visible horizon, the latter always being below the former. Rational horizon, and Sensible horizon.
(Astron.) See def. 2, above. Visible horizon. See definitions 1 and 2, above.