An iceberg
It's called "calving"
iceberg
An Iceberg.
When a piece of a glacier breaks off, it is called calving. This can result in the formation of icebergs.
An ice that breaks off a glacier and floats away is called an iceberg.
A glacier is a piece of ice.
A large detached piece of a glacier is called an iceberg. The process by which this happens is called calving.There isn't really a term for a detached piece of an iceberg. See related question.
A piece of rock can become embedded in the bottom of a glacier through a process called glacial entrainment. As a glacier moves, it erodes the underlying bedrock and picks up sediment, including rocks and debris. This material can become trapped in the ice at the glacier's base, where it is held in place by the pressure of the overlying ice. Over time, as the glacier advances, the rock becomes firmly lodged within the ice.
A glacier is older than an iceberg, because an iceberg is a piece of ice that fell off a glacier.
A floating piece of ice is called an iceberg if it is large and mostly submerged, or an ice floe if it is smaller and more flat or thin.
malaspina glacier
A frozen river is called a frozen river. Rivers that normally flow as liquid water, are called frozen rivers when they become frozen.