Definitions of horn:

• noun:   one of the bony outgrowths on the heads of certain ungulates
• noun:   any outgrowth from the head of an organism that resembles a horn
• noun:   an alarm device that makes a loud warning sound
• noun:   a high pommel of a Western saddle (usually metal covered with leather)
• noun:   a noisemaker (as at parties or games) that makes a loud noise when you blow through it
• noun:   a noise made by the driver of an automobile to give warning;
• noun:   the material (mostly keratin) that covers the horns of ungulates and forms hooves and claws and nails
• noun:   a brass musical instrument with a brilliant tone; has a narrow tube and a flared bell and is played by means of valves
• noun:   a brass musical instrument consisting of a conical tube that is coiled into a spiral and played by means of valves
• noun:   a device on an automobile for making a warning noise
• verb:   stab or pierce with a horn or tusk

  Example: "The rhino horned the explorer"

• name:  A surname (common: 1 in 5000 families; popularity rank in the U.S.: #581)