You feel constricted in general. Remember that the belt is primarily an item that is used for the express purpose of binding something. If you feel that you are too bound by other responsibilities keeping you from acting on your true beliefs and ideas, then something needs to change. Try to imagine what that belt must represent.
For example, let’s say that you work at a secular institution such as a state office, but you are very religious at heart. No matter how much you try to add some of your religious freedom into your workplace, you are told not to and your right to do so is suppressed due to the separation of church and state. You do not feel free to exercise your beliefs and as a result you feel constricted. Thus, in your dream the belt that you are wearing would represent the place that you work.
Let’s say that you are a person who strongly believes in the validity of the theory of evolution, but you are in a relationship with a religious person who refuses to hear any scientific theories on the subject. They would instead prefer to stick to their own theories and not have to worry about hearing any opposition from anyone. These people definitely exist and could cause some others to feel disheartened at not being able to express themselves or their true beliefs. If this sounds like you, then the belt in the dream would represent your significant other, who consistently suppresses your instinct to talk about your scientific background and beliefs.
There are many things that you might want to do in life. We can even go with a less specific situation. Imagine that there are many things that you want to do in your life, but you can’t do any of them because you can’t seem to afford the expenses that they all cost. You cannot go out and surf in the Caribbean and you cannot afford to leave for a few weeks to go on a trip to England all because you have a job and a family to take care of. It also might be hard to afford the trip just because of the money situation that you are in. In this case, the belt in the dream could be representing the plethora of responsibilities that you have such as your family or friends which prevent you from pursuing your dreams currently. The belt could also represent your tight financial obligations which prevent you from progressing any further in life. Even if you can’t afford it in this case, it might be a good idea to go ahead and splurge. After all, life, at its core, is about living. And you don’t want to die knowing that you never got to live your dreams.