Yermak was a Russian and later Soviet icebreaker. It was the first polar icebreaker in the world, having a strengthened hull shaped to ride over and crush pack ice.

An icebreaker is a special-purpose ship or boat designed to move and navigate through ice-covered waters, and provide safe waterways for other boats and ships. Although the term usually refers to ice-breaking ships, it may also refer to smaller vessels, such as the icebreaking boats that were once used on the canals of the United Kingdom.