1880. A. Mitchell, Past in Present, vi. 143. I say this … with a proper amount of ex-cathedral confidence.
Hence Excathedralishly adv., in an official manner, as if with authority.
1831. Blackw. Mag., XXX. 123/2. Before we can possibly understand any thing of Homer, it has been said, ex-cathedralishly, that we must study the manners of the heroic ages.
