Horn
For the instrument—i.e., French horn—see horn (instrument). "Horn" is also used as a slang term for any wind instrument.
A horn is a hollow, pointed projection of the skin of various animals. In ruminant artiodactyls, the horns are paired and take various forms depending on the family:
- Tragulidae: No horns.
- Antilocapridae: The horn has a prong.
- Giraffidae: There are bony bumps covered with furred skin which look like they ought to have horns on them, but do not.
- Cervidae: Deer have antlers, which are not true horns. Made of bone, they are shed and regrown each year.
- Moschidae: Musk deer have no horns, but instead have tusks.
- Bovidae: The horns are made of horn (i.e. keratin) and are cones bent into spiral shapes.
Some peoples use bovid horns as musical instruments, for example the shofar. These have evolved into brass instruments in which, unlike the trumpet, the bore gradually increases in width through most of its length - that is to say, it is conical rather than cylindrical. These are called horns, though made of metal. See horn (instrument).
Rhinoceros "horns" are actually compacted hair; not true horn.
In telecommunication, the term horn has the following meanings:
- In radio transmission, an open-ended waveguide, of increasing cross-sectional area, which radiates directly in a desired direction or feeds a reflector that forms a desired beam.
- Note 1: Horns may have one or more expansion curves, i.e., longitudinal cross sections, such as elliptical, conical, hyperbolic, or parabolic curves, and not necessarily the same expansion curve in each (E-plane and H-plane) cross section.
- Note 2: A very wide range of beam patterns may be formed by controlling horn dimensions and shapes, placement of the reflector, and reflector shape and dimensions.
- A portion of a waveguide in which the cross section is smoothly increased along the axial direction.
- In audio systems, a tube, usually having a rectangular transverse cross section and a linearly or exponentially increasing cross-sectional area, used for radiating or receiving acoustic waves. (Source: from Federal Standard 1037C and from MIL-STD-188). These devices perform a mechanical impedance matching for acoustic energy.
- Fixed radio telescope, originally built to observe certain objects in the sky, preceded the more commonly known movable dishes used today.
In phonetics, the term horn is used for a diacritic mark attached to the top right corner of the letters o and u in the Vietnamese alphabet to give ơ and ư, unrounded variants of the vowel represented by the basic letter.
The HTML/Unicode numbers for letters with a horn are:
Places called Horn include: