Legendary monster usually depicted as a huge, bat-winged, fire-breathing lizard or snake with a barbed tail. The dragon symbolized evil in the ancient Middle East, and the Egyptian god Apepi was the great serpent of the world of darkness. The Greeks and Romans sometimes represented dragons as evil creatures and sometimes as beneficent powers acquainted with the secrets of the earth. In Christianity the dragon symbolized sin and paganism, and saints such as St. George were shown triumphing over it. Used as warlike emblems in many cultures, dragons were carved on the prows of Norse ships and depicted on royal ensigns in medieval England. In the Far East the dragon was a beneficent creature, wingless but regarded as a power of the air. In China it symbolized yang in the yin-yang of cosmology, and it served as the emblem of the royal family.