Floe (noun)

1. A flat piece of ice floating in the sea or a river.
2. A flat piece of ice floating on a body of water, especially in the Arctic or Antarctic.

Origin:

Early 19th century: from old norse flói.

Examples:

1. The ship was surrounded by floes of ice.
2. The floes broke off from the glacier and floated out to sea.
3. The polar bear was spotted on a floe hunting for food.
4. The floes were a danger to the ships navigating through the frozen water.
5. The floes were constantly shifting, making it difficult for the icebreaker to proceed.