1. play that involves interacting with others for fun or sport. Examples include rough-and-tumble play and sometimes sociodramatic play. It is one of three basic types of play traditionally identified, the others being object play and locomotor play. Often considered primarily a human activity, social play also occurs among many nonhuman animals, including fish, reptiles, amphibians, insects, nonhuman mammals, and others. For example, some fish physically tease each other, and wasps engage in mock fighting.

2. patterns of play identified by the 1932 classification system of U.S. child-development researcher Mildred Parten and used to characterize the level of social development and participation of preschool children. The lowest level of this system is solitary play, in which a child is near others but focused on his or her own activity; it progresses to parallel play, in which a child is next to others and using similar objects but still engaged in his or her own activity. The latter is succeeded by associative play, in which a child interacts with others but there is no common purpose or organization to the shared activity, and the series culminates in the highest level, cooperative play, in which a child interacts with others in coordinated, directed activities.