1. any one of various imperial decrees with the effect of fundamental law.
2. (caps.) Hist. a. any of several imperial or royal decrees limiting the power or privilege of the papacy, as the decree of Charles VII of France in 1438 or that of the Diet of Mainz in 1439.
b. the imperial decree of Charles VI of Austria in 1713, by which his daughter, Maria Theresa, inherited his dominions.