roleplaying game

Short definition from Wiktionary

Noun

1. 1
   A type of game where one or more players assume the roles of characters (usually one each) to interact with a fictional world either defined by themselves or through the moderation of a neutral judge (usually referred to as the game master).
2. 2
   A type of computer game where the player takes the role of a character or party, normally lacking tests of physical skill and including more story-telling and narrative aspects than traditional action games.