Entertaiment means the activity of providing amusement, diversion, or pleasure. It includes any activity that is a source of enjoyment or delight, whether it is an art form such as theatre, a game such as chess, or a work of fiction such as a novel. It also consists of activities such as eating, drinking and socialising that are intended to give pleasure to the senses.
The word entertainment comes from the Medieval Latin intertenere, which in turn is derived from the Indo-European root ten, meaning to stretch or extend. It is interesting to note that entertainment often focuses on themes the human brain was evolved to deeply react to, such as backstabbing or murder.