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A cathedra is the bishop’s chair or throne in his or her cathedral church. It was originally situated in the centre of the apseSemicircular or polygonal termination of the chancel, which is typically situated at the eastern end of a Christian church., behind the high altar, but from the Middle Ages was often installed to one side of the chancelPart of a church containing the altar, used by the officiating clergy..[1] The term is a borrowing from the Latin cathedra, meaning “chair”.[2]
The phrase “ex cathedra” – literally “from the chair” – is used more generally in reference to the utterances of anyone speaking from a position of authority,[2] and in particular the Catholic Church’s doctrine of papal infallibility,[1] which was proclaimed at the First Vatican Council by Pius IX in 1870.[3]