Major, important.
Of or relating to an artery.
A through road.
Of or relating to an epic.
Momentously heroic; grand in scale or character
That is an epimorphism.
Extending beyond the usual or ordinary.
In software development, a large or extended user story.
A series of events considered appropriate to an epic.
An extended narrative poem in elevated or dignified language, celebrating the feats of a deity, demigod (heroic epic), other legend or traditional hero.