Music A brass wind instrument, such as a trombone or tuba. Music A wind instrument made of an animal horn. One of the hard, usually permanent structures projecting from the head of certain mammals, such as cattle, sheep, goats, or antelopes, consisting of a bony core covered with a sheath of keratinous material. A hard protuberance, such as an antler or projection on the head of a giraffe or rhinoceros, that is similar to or suggestive of a horn. The hard smooth keratinous material forming the outer covering of the horns of cattle or related animals. A natural or synthetic substance resembling this material. A container, such as a powder horn, made from a horn. Something having the shape of a horn, especially: A horn of plenty; a cornucopia. Either of the ends of a new moon. The point of an anvil. The pommel of a saddle. An ear trumpet. A device for projecting sound waves, as in a loudspeaker. A hollow, metallic electromagnetic transmission antenna with a circular or rectangular cross section. Music A French horn. Music A wind instrument, such as a trumpet or saxophone, used in a jazz band. A usually electrical signaling device that produces a loud resonant sound: an automobile horn. Any of various noisemakers operated by blowing or by squeezing a hollow rubber ball. Slang A telephone. To join without being invited; intrude. Used with in. blow Informal To brag or boast about oneself. draw Informal To restrain oneself; draw back. draw Informal To retreat from a previously taken position, view, or stance. draw Informal To economize.