obstinate rebelliousness and insubordination; resistance to authority

Contumacy is the stubborn or willful disobedience of one's lord. The guilty party would forfeit their fief and, at times, even be excommunicated.

Contumacy, in ecclesiastical law, is contempt of the authority of an ecclesiastical court and is dealt with by the issue of a writ from the Court of Chancery at the instance of the judge of the ecclesiastical court. This writ took the place of the de excommunicato capiendo in 1813, by an act of George III; see excommunication.