horn

noun

1. 1.

   A hard permanent outgrowth, often curved and pointed, found on the heads of cattle, sheep, goats, and other animals.

2. 2.

   A brass wind instrument, typically with a curved tube and a flared bell.

3. 3.

   A device on a vehicle used to make a warning sound.

4. 4.

   A projection or extremity shaped like an animal's horn.