>>91931277Omniverse, Macroverse and stuff like that are concepts thrown around with little care, cue that page where superman exorcised a phantom planet from earth and people called it "saving the omniverse".
A Multiverse is comprised of several universes, but let's say that if you add up each universe's volume into a single universe, one so big that has the size of a multiverse and is just one, I would call that a Macroverse; however a multiverse doesn't take into account different realities, realms, "dimensions" and maybe even timelines, so the entirety of Marvel reality could be called an Omniverse since it encompasses everything related to it, multiversal or not.
Take into consideration DC Comics, the multiverse is comprised by 52 universes, but the sphere of the gods is not a part of the multiverse, neither is the Monitor Sphere, it all would, in my opinion, be called an Omniverse.