ice sheet
From Longman Dictionary of Contemporary EnglishRelated topics: Geography, Oceanographyice sheetˈice sheet noun [countable] SGan ice capExamples from the Corpusice sheet• The cutter rolls briefly as it splits an ice sheet the size of a suburban back yard.• No doubt the ice sheet preserves specimens that would weather away more quickly in other regions.• The tremendous weight of the ice sheet loaded and depressed that part of the lithosphere.