The word "chord" has an interesting origin. In Middle English, the word was spelled "corde" and referred to animal intestines. Since twine was made from them, the word was also closely related to "cord," referring to a piece of string or rope. These "guts" were used to form the strings for musical instruments. When two or more were struck simultaneously, the player was striking or playing cordes. Later the spelling was changed to "chord," and a legitimate one had to contain at least three different tones. Oddly, the crude barbershop term for a well-rung chord, a "gut buster," refers back to the Middle English.