c.1205, title placed before a name and denoting knighthood, from O.Fr.
sire, from V.L.
*seior, from L.
senior "older, elder" (see
senior). Standing alone and meaning "your majesty" it is attested from c.1225. General sense of "important elderly man" is from 1362; that of "father, male parent" is from c.1250. The verb meaning "to beget, to be the sire of" is attested from 1611, from the noun.
[sahyuh
r] 
noun, verb, sired, sir⋅ing.