Ice cap, ice sheet, polar ice cap
An ice cap is a dome-shaped mass of glacier ice that spreads out in all directions; usually larger than an icefield but less than 50 000 km2.
An ice sheet is a dome-shaped mass of glacier ice that covers surrounding terrain and is greater than 50 000 km2, such as the Greenland and Antarctic ice sheets.
A polar ice cap, also called polar ice sheet, is a high-latitude region of land or water covered in ice-
Ice cap in Ellesmere Island, Canada
Source: based on NSIDC Cryosphere Glossary