antipapacy

And as for the perſecution of the Empreſſe which happened long before, and for an other cauſe, to witt, foraſmuch as Vigilius after his predeceſſor Siluerius was dead, and that he was become true Pope, would not keepe the promiſe that he had made, and ſecretlie accomplisht to her during his Antipapacy, to admitt Anthymus and the other Eutychians into his communion.

1630, The Reply of the Most Illustrious Cardinall of Perron, to the Ansvveare of the Most Excellent King of Great Britaine, first tome, […] Martin Bogart, […], page 254

[…] instead of thoroughgoing reforms, the actions of that council culminated in the formation of another—the last—antipapacy (Felix V, reigned 1439–49).

1983, The New Encyclopædia Britannica, page 1008, column 2

But with the end of the papacy, or antipapacy, of Benedict XIII, whether by the deposition decreed by the Council of Constance in 1417 (which Benedict rejected) or by his death in 1423 (which he had to accept), no more popes chose Avignon for their principal residence.

2001, John Deely, Four Ages of Understanding: The First Postmodern Survey of Philosophy from Ancient Times to the Turn of the Twenty-first Century, Toronto, Ont.; Buffalo, N.Y.; London: University of Toronto Press, →ISBN, page 398