VATICAN COUNCIL • DICTIONARY ONE.COM • Definition of Vatican Council

... fact, science, or general opinion. The seat of infallibility has been much disputed even in the Roman Catholic Church itself, and the infallibility of the Pope was only decreed so recently as the Vatican Council in 1870. It was always agreed that where the Pope and Bishops were unanimous they were infallible, and their unanimity might be expressed either in a general council, or in a decree of a local council tacitly accepted by the Pope ...

— The Nuttall Encyclopaedia - Being a Concise and Comprehensive Dictionary of General Knowledge • Edited by Rev. James Wood