Vatican Council, a Church council attended by 764 ecclesiastics under the auspices of Pius IX., which assembled on December 8, 1869, and by a majority of nearly 481 decreed the doctrine of Papal Infallibility.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Vatican, The * Vauban, Sebastien le Prestre de