Leon (Ancient Greek: λέων, romanized: léon; leōn) is a first name of Greek origin, meaning "lion". It gave rise to similar names in other languages, including the Latin Leo, French Lyon or Léon, Irish Leon, Spanish León, Levon Լեվոն Armenian or Georgian Levan / ლევან.
In Greek mythology, Leon was a giant killed by Heracles. One of the oldest attested historical figures to bear this name was Leon of Sparta, a 6th-century BCE king of Sparta. During the Christian era, the name Leon was merged with the Latin cognate Leo, with the result that the two forms are used interchangeably.[1]
A similar Greek name, Leonidas, means "son of a lion". Leonidas I, king of Sparta, was a famous bearer of that name.
The Ancient Greek word λέων ultimately comes from Proto-Semitic *labiʾ-, which is not Indo-European.