Paladin

Here are some possible meanings of a paladin:

• In historical terms, a paladin is one of the twelve legendary knights who served as the closest companions of Charlemagne, the king of the Franks and the first emperor of the Holy Roman Empire in the 8th century.
  These paladins, also called the Twelve Peers, were heroes of the medieval chanson de geste cycle of the Matter of France, where they fought against the Saracen invasion of Europe.
  Some of the most famous paladins were Roland, Oliver, Ogier, and Archbishop Turpin.
• In fantasy literature and games, a paladin is a holy warrior who fights for a righteous cause, often with divine powers and magic.
  Paladins are usually associated with the virtues of chivalry, honor, justice, and faith.
  They often serve as protectors of the weak, defenders of the faith, and enemies of evil.
  Some examples of paladins in fiction are Sir Galahad from Arthurian legend, Arthas Menethil from Warcraft, and Cecil Harvey from Final Fantasy IV.
• In modern usage, a paladin is a loyal and courageous supporter or champion of a noble cause, person, or organization.
  The word is often used to describe someone who is devoted to a leader, a principle, or a mission.
  Some synonyms of paladin are crusader, advocate, hero, and knight.
  For instance, one could say that Nelson Mandela was a paladin of human rights, or that the paladins of Microsoft are working hard to improve their products.

As you can see, a paladin can look very different depending on the situation.

However, a common trait of all paladins is that they are brave, loyal, and dedicated to a higher purpose.