What's the difference between i.e. and e.g.?
1510s, from French monsieur, from mon sieur "my lord," from sieur "lord," shortened form of seigneur (see monseigneur) It was the historical title for the second son or next younger brother of the king of France.
the French equivalent both of "sir" (in addressing a man directly) and of "mister," or "Mr." Etymologically it means "my lord" (mon sieur).