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Old English horn "horn of an animal," also "wind instrument" (originally made from animal horns), from Proto-Germanic *hurnaz (cf. German Horn, Dutch horen, Gothic haurn), from PIE *ker- "horn; head, uppermost part of the body," with derivatives refering to horned animals, horn-shaped objects and projecting parts (cf. Greek karnon "horn," Latin cornu "horn," Sanskrit srngam "horn," Persian sar "head," Avestan sarah- "head," Greek koryphe "head," Latin cervus "deer," Welsh carw "deer"). Reference to car horns is first recorded 1901. Figurative senses of Latin cornu included "salient point, chief argument; wing, flank; power, courage, strength." Jazz slang sense of "trumpet" is by 1921. Meaning "telephone" is by 1945.
1690s, "to furnish with horns," from horn (n.). Earlier in figurative sense of "to cuckold" (1540s). Meaning "to push with the horns" (of cattle, buffalo, etc.) is from 1851, American English; phrase horn in "intrude" is by 1880, American English, originally cowboy slang.
One of the hard, usually permanent structures projecting from the head of certain mammals, such as cattle, consisting of a bony core covered with a sheath of keratinous material.
A hard protuberance that is similar to or suggestive of a horn.
The hard, smooth keratinous material forming the outer covering of animal horns.
Any of the major subdivisions of the lateral ventricle in the cerebral hemisphere of the brain: the frontal horn, occipital horn, and temporal horn. Also called cornu.
Trumpets were at first horns perforated at the tip, used for various purposes (Josh. 6:4,5). Flasks or vessels were made of horn (1 Sam. 16:1, 13; 1 Kings 1:39). But the word is used also metaphorically to denote the projecting corners of the altar of burnt offerings (Ex. 27:2) and of incense (30:2). The horns of the altar of burnt offerings were to be smeared with the blood of the slain bullock (29:12; Lev. 4:7-18). The criminal, when his crime was accidental, found an asylum by laying hold of the horns of the altar (1 Kings 1:50; 2:28). The word also denotes the peak or summit of a hill (Isa. 5:1, where the word "hill" is the rendering of the same Hebrew word). This word is used metaphorically also for strength (Deut. 33:17) and honour (Job 16:15; Lam. 2:3). Horns are emblems of power, dominion, glory, and fierceness, as they are the chief means of attack and defence with the animals endowed with them (Dan. 8:5, 9; 1 Sam. 2:1; 16:1, 13; 1 Kings 1:39; 22:11; Josh. 6:4, 5; Ps. 75:5, 10; 132:17; Luke 1:69, etc.). The expression "horn of salvation," applied to Christ, means a salvation of strength, or a strong Saviour (Luke 1:69). To have the horn "exalted" denotes prosperity and triumph (Ps. 89:17, 24). To "lift up" the horn is to act proudly (Zech. 1:21). Horns are also the symbol of royal dignity and power (Jer. 48:25; Zech. 1:18; Dan. 8:24).