Quests are a common way for games to add content into their experiences. For this reason, procedural generation of quests has become a popular area of research in recent years. However, in academia there is no consensus on the definition of a quest, despite many researchers attempting to generate them. The purpose of this paper is to do a literature survey of quest definitions in the context of procedural quest generation, and synthesize the different versions into a more general definition that encompasses existing definitions.