plage noun \ ˈpläzh \ Definition of plage 1: the beach of a seaside resort 2: a bright region on the sun caused by the light emitted by clouds of calcium or hydrogen and often associated with a sunspot Did You Know? The history of plage begins with the Greek word plagios, meaning "sideways" or "oblique," and then moves over to Late Latin as plagia. It arrived on the shores of southern Italy in the form of Italian piaggia and was used of the beaches there. It became plage in French and coasted into the English language in 1888. The...