What do large plates of floating glacial ice refer to?

Large plates of floating glacial ice are referred to as ice shelves. Ice shelves are extensions of continental ice sheets that have flowed out over the ocean and float on the water's surface. They are formed by the accumulation of snow and ice over time and can be quite extensive, covering vast areas of the sea surface. Ice shelves can play a significant role in the dynamics of the ice sheets they are connected to, as they act as barriers that slow the flow of glaciers into the ocean.

In contrast, icebergs are chunks of ice that have calved from glaciers or ice shelves and float in open water. They are typically smaller than ice shelves and can be found drifting in oceans and seas. Ice sheets are massive, continuous expanses of ice that cover large land areas, such as the Antarctic or Greenland ice sheets. Glacial erratics refer to rock fragments that have been transported by glacial ice and deposited in a different location than their source, and do not pertain to floating ice structures. Hence, the appropriate term for large floating plates of glacial ice is ice shelves.