In days of old when knights were bold, Anglo-French speakers used the word chevaler (an ancestor of our word chevalier) for a knight or horseman. By the 14th century, English speakers had adopted the slightly modified spelling chivalry to describe their own well-armored, mounted warriors. Nowadays, when we say that chivalry is not dead, we are alluding to the high standard of character and conduct typically associated with gallant knights. If you trace chevaler back to Late Latin, you'll find that it derives from caballarius, which is also the ancestor of another term for a daring medieval gentleman-at-arms: cavalier.