Wiktionary
n. (context Canada English) The dialect of working-class Quebecers.
Wikipedia
Joual is the common name for the linguistic features of basilectal Quebec French that are associated with the French-speaking working class in Montreal which has become a symbol of national identity for a large number of artists from that area. Speakers of Quebec French from outside Montreal usually have other names to identify their speech, such as Magoua in Trois-Rivières, and Chaouin south of Trois-Rivières. Linguists tend to eschew this term, but historically some have reserved the term joual for the variant of Quebec French spoken in Montreal.
Like most regional and class variants of a widely spoken language, joual is stigmatized by some and celebrated by others. While joual is often considered a sociolect of the Québécois working class, that perception is outdated. Both the upward socio-economic mobility among the Québécois, and a cultural renaissance around joual connected to the Quiet Revolution in the Montreal East-End have resulted in joual being spoken by people across the educational and economic spectrum. Today, many Québécois who were raised in Quebec during the last century (command of English notwithstanding) can understand and speak at least some joual.