noun An act of changing physical location or position or of having this changed. (a slight movement of the upper body) A change or development. (movements in the underlying financial markets) A group of people working together to advance their shared political, social, or artistic ideas. (the labor movement) A principal division of a longer musical work, self-sufficient in terms of key, tempo, and structure. (the slow movement of his violin concerto) An act of defecation.