Sir

Honorific title

Sir is a formal honorific address in English for men, derived from Sire in the High Middle Ages. Both are derived from the old French "Sire" (Lord), brought to England by the French-speaking Normans. Traditionally, as governed by law and custom, Sir is used for men who are knights and may belong to certain orders of chivalry, as well as later applied to baronets and other offices.

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