Before revision: Dialect levelling or leveling ( in American English) is the process of an overall reduction in the variation or diversity of features in a dialect due to contact with one or more other dialects .Britain, David (2010).
After revision: Dialect levelling (or leveling in American English) is the process of a dialect increasingly adopting features with widespread social currency at the expense of more local or traditional features, due to contact with one or more other dialects .Britain, David (2010).