In heraldry, cadency's any systematic way of distinguishing similar coats of arms belonging to members of the same family. Cadency's necessary in heraldic systems in which a given design may be owned by only one person (or, in some cases, one man) at once. Because heraldic designs may be inherited, the arms of members of a family will usually be similar to the arms used by its oldest surviving member (called the "plain coat"). They're formed by adding marks called brisures, similar to charges b… (
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