What is of or pertaining to augurs or to augury; betokening; ominous; significant; as, an augural staff; augural books. "Portents augural." Cowper called?

augural — Of or pertaining to augurs or to augury; betokening; ominous; significant; as, an augural staff; augural books. "Portents augural." Cowper. (Webster's 1913.)

Sources