noun
: an area (as in Wisconsin and parts of Minnesota, Illinois, and Iowa) that is free from glacial drift and seems not to have been covered by the Pleistocene ice
noun
: an area (as in Wisconsin and parts of Minnesota, Illinois, and Iowa) that is free from glacial drift and seems not to have been covered by the Pleistocene ice
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012