horn

(countable) A hard growth of keratin that protrudes from the top of the head of certain animals, usually paired.

Any similar real or imaginary growth or projection such as the elongated tusk of a narwhal, the eyestalk of a snail, the pointed growth on the nose of a rhinoceros, or the hornlike projection on the head of a demon or similar.

An antler.

(uncountable) The hard substance from which animals' horns are made, sometimes used by man as a material for making various objects.

The high pommel of a saddle; also, either of the projections on a lady's saddle for supporting the leg.

(architecture) The Ionic volute.

(nautical) The outer end of a crosstree; also, one of the projections forming the jaws of a gaff, boom, etc.

(carpentry) A curved projection on the fore part of a plane.

One of the projections at the four corners of the Jewish altar of burnt offering.

(countable) Any of several musical wind instruments.

(countable, music) An instrument resembling a musical horn and used to signal others.

(countable, automotive) A loud alarm, especially one on a motor vehicle.

(chiefly sports) A sound signaling the expiration of time.

(countable) A conical device used to direct waves.

(informal, music, countable) Generally, any brass wind instrument.

(slang, countable, from the horn-shaped earpieces of old communication systems that used air tubes) A telephone.

(uncountable, vulgar, slang, definite article) An erection of the penis.

(countable, geography) A peninsula or crescent-shaped tract of land.

(countable) A diacritical mark that may be attached to the top right corner of the letters o and u when writing in Vietnamese, thus forming ơ and ư.

(botany) An incurved, tapering and pointed appendage found in the flowers of the milkweed (Asclepias).

(military) In naval mine warfare, a projection from the mine shell of some contact mines which, when broken or bent by contact, causes the mine to fire.