Physics question

At first a little bit of a 'de-amazer':
Physics is not about explaining things. So the question "What is the fourth dimension?" will never be answered by physicists.
Physics is about describing things. That in essence means, you can define the fourth dimension to be what ever you want it to be. But physics is also about describing things and bringing them together with the building blocks that have been laid down so far. In order to be consistent with the rest of physics time is most often referred to as being the fourth dimension.

When you hear that the fourth dimension is time with respect to relativity what is actually meant is that in relativity you give the position and time of an event with a 4 component vector, the ordering of components within that vector is arbitrary, you could just as easily say the first dimension is time. The 'fourth dimension' can refer to another spatial dimension as well it just depends upon the context. The fourth dimenson is nothing special it just appears when whatever maths you're doing to model something requires four or more dimensions (e.g. you need a coordinate system with 4 or more components for some reason).

Dimensions 5 through 11 are supposedly microscopic (many many many times smaller than atoms) loops, where, being a loop, any movement along one would eventually bring you back to where you started, and being so incredibly small, nobody could see any movement in them anyway.

Actually, I'm lying. Don't listen to anything I have to say. Ever. Even this very paragraph.

my math teacher (a very smart guy) always told me that there are an infinite number of dimensions (on a theoritical level). However, if you are talking about one dimension as width, one as height, one as depth, to me time as another dimension only makes sense. In the real world a 3d position is almost completely meaningless unless you know it's time value. What good is knowing your GPS position and height if you stood at that spot a week ago? All positions are relative to a time. That's my opinion anyway, i doubt you will fin d a consensus