Dreaming of an armpit means bearing your true form to the public. There is nothing holding you back in terms of your true attitude and personality. If an armpit is untrimmed, you are likely to be wild and nonconforming to socially acceptable etiquette. The reverse is true if your armpit has been shaved.
Some people think that an armpit in a dream represents vulnerability. It may signify feeling exposed or unprotected in some way, either because you feel like others can see right through you or because you are showing too much of yourself to others.
Others think that an armpit in a dream signifies being unclean or having dirty thoughts. In this case, the person might be feeling guilty about his or her actions or thoughts and trying to suppress those feelings by applying deodorant.