Sire is a title used to refer to a knight or baronet, as well as the father of a man or the master of a house. The title is used in several ways. The first way is to refer to a person of general importance, a member of the nobility or royalty. For example, the title is used to refer to the king, duke, earl, viscount, baron, etc. It is also used to refer to the general of an army, the admiral of a navy, the general of a police force, the commander of a military unit, or the leader of a religious order. However, the word sire is now considered archaic and it's mostly used to refer to a male horse producing offspring. The term sir is now used as a title to address a man of high social status. For example, a person may be addressed as "sir" by a member of the royal family, or by a member of the aristocracy.