Mob : a large crowd of people, especially one that is disorderly and intent on causing trouble or violence. Group : a number of people or things that are located, gathered, or classed together. Family : a group consisting of two parents and their children living together as a unit. Institution : an organization founded for a religious, educational, professional, or social purpose. Coterie : a small group of people with shared interests or tastes, especially one that is exclusive of other people.