Sire can refer to several things:

• Sire is how one spells "Eris" backwords.
• Sire is a term for the father (or genetic species providing sperm) of a creature, contrasting to the female term, dam.
  For example, the sire of a mule would be a donkey, and the dam of a mule would be a horse.
• Sire is used as a form of address and title for a man of rank or authority, equivalent to Lord or Prince.
• Sire Records is a record label.
• In vampire mythology and fiction, a vampire's sire is the vampire that turned him or her into a vampire (which is now his or her childe).

In the case of the fictional Buffyverse see here.

Grandsire is the term for the sire of a sire, much like grandfather or grandmother. In its common modern meaning, a mule is the offspring of a male donkey and a female horse. ... Binomial name Equus asinus Linnaeus, 1758 For other uses, see Donkey (disambiguation). ... Binomial name Equus caballus Linnaeus, 1758 nugget For other uses, see Horse (disambiguation). ... A lord is a male who has power and authority. ... The term prince (the female form is princess), from the Latin root princeps, when used for a member of the highest aristocracy, has several fundamentally different meanings - one generic, and several types of titles. ... Sire Records Company is an American record label, owned by Warner Music Group and distributed through Warner Brothers Records The label was founded in 1966 as Sire Productions by Seymour Stein and Richard Gottehrer. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Philip Burne-Jones, The Vampire, 1897 Vampires are mythical or folkloric creatures, typically held to be the re-animated corpses of human beings and said to subsist on human and/or animal blood (hematophagy), often having unnatural powers, heightened bodily functions, and/or the ability to physically transform. ... In White Wolf Game Studios Vampire: The Masquerade books and role-playing games, a childe ( childer) is the vampiric offspring of another vampire, referred to as the sire. ... The Buffyverse is a term coined by fans of Joss Whedons first two television shows to refer to the shared fictional universe in which they are set. ... In the fictional world of the television series Buffy the Vampire Slayer and Angel, a vampire is a demon of a species which inhabits and animates a human corpse. ...

• According to the Department of Canadian Heritage, the title of sire is given in conversation with a male monarch (king or emperor). http://www.canadianheritage.gc.ca/progs/cpsc-ccsp/pe/address4_e.cfm