Entertainment is a form of cultural activity. It can be consumed by individuals and adapted to any scale. It is objective, encompasses communication between text and audience, comes from external stimulus, offers pleasure, requires an audience and happens in a passive form. It can take many forms: a clown at a birthday party; a Broadway show; a stadium rock concert; your friends fighting over the last potato chip.
From the Old French entretenir, to hold together or support; related to hospitality—when you entertain guests, you keep them happy. Also a pleasing or agreeable occupation of the mind, diversion, or amusement: playing the daily crossword is my entertainment.