These Facts Toot Their Own Horn

Sunday
Anatomically speaking, horns aren’t antlers and vice versa. Antlers fall off each year and regrow the next, but horns stay put (with the exception of the pronghorn) and grow throughout the animal’s life.
Monday
Before musical horns were metal, they were made of animal horns, hence the name.
Tuesday
Powder horns, where gunpowder was stored and kept dry for Colonial-era weapons, also came from animals, typically cattle.
Wednesday
Before they were more often metal or plastic, shoehorns were made from – you guessed it – animal horn.
Thursday
The term “horny” derived from “having the horn,” a slang term for an erection. Though it previously applied to just men, it now describes arousal in any gender.
Friday
“Greenhorn” is an inexperienced (and often naive) person, since the new horns of young oxen (and by another possible source, the color when an inexperienced jeweler used the wrong temperature to process a piece of horn jewelry).
Saturday
The familiar horned appearance of the Christian devil is largely influenced by the appearance of the Greek god Pan, which itself is informed by the Egyptian god Bes.