Originally a short form of names ending with the Old German element helm meaning "helmet, protection", such as Guglielmo or Anselmo. It is also a derivative of Erasmus, via the old Italian short form Ermo. Saint Elmo, also known as Saint Erasmus, was a 4th-century martyr who is the patron of sailors. Saint Elmo's fire is said to be a sign of his protection.In the English-speaking world this name is now associated with a red muppet character from the children's television program Sesame Street.