To experience deployment is to be forced to leave to another area or to be ordered to leave for a new area.
Dreaming of deployment means that you think that your life is fairly stressful. Deployment is usually a word associated with the army and it can be referring to one of two things. Deployment could be the process of being contacted by the army, having all of these army things filled out, and then having you sent to the country or location in which you were meant to serve. Deployment could also mean that you have already been sent out to the place where you are meant to serve, and there is a battle going on where you are. Here deployment could be referring to being carried out to the area where this battle is actually taking place, and being set out of the helicopter or plane or whatever the vehicle is, ready to fight as soon as you set down. Either way, dreaming of deployment means you are in an intense area of conflict in your life and you are trying to sort through it. Don’t worry too much about it, just try to focus on the future and don’t think about how awful the present is.