A
golden bull or
chrysobull was a golden
seal (a
bulla aurea), attached to a
decree issued by
Byzantine Emperors and later by monarchs in Europe during the
Middle Ages and
Renaissance. The term was originally coined for the golden seal itself but came to be applied to the entire decree. Such decrees were known as golden bulls in western Europe and
chrysobullos logos, or chrysobulls, in the Byzantine Empire (χρυσός,
chrysos, being
Greek for
gold).