Webster's Revised Unabridged Dictionary · 1913

Diagonial

Diagonial , adjective

Diagonal; diametrical; hence; diametrically opposed. [Obsolete]
Sin can have no tenure by law at all, but is rather an eternal outlaw, and in hostility with law past all atonement; both diagonal contraries, as much allowing one another as day and night together in one hemisphere. — Milton