What is the meaning of Hero?

noun

• A man distinguished by exceptional courage and nobility and strength.
  • usage: "RAF pilots were the heroes of the Battle of Britain"
• The principal character in a play or movie or novel or poem.
• Someone who fights for a cause.
  • synonyms: champion, fighter, paladin
• Greek mathematician and inventor who devised a way to determine the area of a triangle and who described various mechanical devices (first century.
  • synonyms: Heron, Hero of Alexandria
• Classical mythology. ( a being of great strength and courage celebrated for bold exploits; often the offspring of a mortal and a god)
• Greek mythology. ( priestess of Aphrodite who killed herself when her lover Leander drowned while trying to swim the Hellespont to see her)
• A large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States.
  • synonyms: bomber, grinder, hero sandwich, hoagie, hoagy, Cuban sandwich, Italian sandwich, poor boy, sub, submarine, submarine sandwich, torpedo, wedge, zep