To dream that you are in your underwear signifies a situation that has created a loss of respect for you. Alternatively, it symbolises some aspect of yourself that is private. If you feel ashamed of being seen in your underwear, then it indicates your hesitance in revealing your true feelings, attitudes, and other hidden habits/ideas. If you are not bothered by being in your underwear, then it suggests that you are ready to reveal or expose something that was previously hidden.
To dream that you are not wearing any underwear signifies fear that your secrets will be revealed.
To dream that someone is in their underwear signifies an embarrassing and inexplicable situation. Alternatively, the dream means that you are seeing this person for who he or she really is.
To see dirty or torn underwear suggests that you are not comfortable in your own skin and have feelings of inadequacy. You are uncomfortable about your sexuality and are overly critical about yourself.