Definitions:
a hard permanent outgrowth, often curved and pointed, found in pairs on the heads of cattle, sheep, goats, giraffes, etc. and consisting of a core of bone encased in keratinized skin.

the substance of which horns are composed

a horn-shaped projection or object.

a wind instrument, conical in shape or wound into a spiral, originally made from an animal horn (now typically brass) and played by lip vibration.

a device sounding a warning or other signal

(of an animal) butt or gore (someone or something) with the horns.

be unfaithful to (one's husband or wife).