Origins of the Caduceus

• In ancient Greek mythology, the divine messenger Hermes came upon two snakes fighting. Using his staff, he separated them and thereafter a staff entwined by snakes became a sign of peace and Hermes' symbol. The wings atop the staff represent his role as the divine winged messenger.
  
  

Etymology

• The Latin word "caduceum" originates from the Greek "kerukeion," meaning "herald's staff." In Latin, a "caduceator" is a diplomatic negotiator. The Romans however, did not reference the Greek god Hermes in connection with the caduceus; rather, they used the Roman equivalent, Mercury.
  
  

The Caduceus and Medicine

• The caduceus has become associated in the past with medicine. This is an erroneous adoption, as mythologically the caduceus was never connected with healing or medicine. The caduceus is confused with the rod of Asclepius, the god of medicine, which is a staff entwined with one snake and has no wings mounted on top.
  
  

Other Origins

• Another mythological origin of the caduceus is in the tale of Tiresias, who came upon two snakes copulating. Killing the female with his staff, he was transformed into a woman and remained one for seven years. The curse was lifted when Tiresias came upon two other snakes fighting. He was transformed back into a man when he killed the male snake with the same staff he had killed the female with seven years earlier.
  
  

Modern Usage

• The caduceus is sometimes seen as a printer's mark in books. The adoption of the symbol by printers came about because of the caduceus being the emblem of Hermes as a messenger and herald.