To dream that you are in an enclosure suggests that you are on guard. There is a circumstance that makes you feel on edge and that you must protect your interests.
To dream that you are in a shrinking enclosure suggests that you are being held back or kept down in a situation. This dream signifies the restrictions that may be genuine or simply felt. Experiment with these restrictions so that you can experience growth.
To dream that you are in a glass enclosure indicates that you are being overly censorious about a particular individual or circumstance.