Longman Dictionary of Contemporary English - expulsion

~ n 1 the process of sending a person or group of people away from a place often by using force  (the expulsion of rebel forces) 2 the act of sending someone away from a school or organization so that they can no longer go there or be a member  (Tina's anti-social behaviour eventually led to her expulsion.) 3 the act of getting rid of a substance from your body or from a container  (- see also expel)