Time is a 4th dimension when talking about spacetime, which assumes three dimensions of space and one dimension of progressing time.
Yeah, that's basically what I was referring to. Everything I know about dimensions, I learned from Doctor Who, Hitchhiker's Guide to the Galaxy and Donnie Darko!
stabs pencil through folded paper to illustrate wormhole
FWIW our current understanding of spacetime includes multi-dimensional time, which is why we experience more or less time when we are traveling at high speed or experiencing strong gravitational fields. It's sort of like moving diagonally across a room, except entirely different.
I know, that's why I said it's entirely different.
But also, we don't know exactly how time dilation works. We know it does, because it makes sense mathematically and we have experienced it in applications, but we don't really know how it works.
I like to work from the assumption that there's nothing magic about the three dimensions we live in aside from the fact that it's how it is, so any higher dimensions would work just like the three we already have, which are identical to each other just in different directions.