pack ice

American  

noun

1. a large area of floating ice formed over a period of many years and consisting of pieces of ice driven together by wind, current, etc.

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pack ice British  

noun

1. Also called: ice pack.  a large area of floating ice, usually occurring in polar seas, consisting of separate pieces that have become massed together

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pack ice Scientific  

/ păk /

1. The floating sea-ice cover of the polar regions. Driven by winds and ocean currents, pack ice is a mixture of ice fragments of varying size and age that are squeezed together and cover the sea surface with little or no open water. At maximum expansion during the winter, pack ice covers about five percent of Arctic waters and about eight percent of Antarctic waters.

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Etymology

Origin of pack ice

First recorded in 1840–50

Example Sentences

Seals rely on pack ice to give birth, to rest and for protection.

From Barron's • Feb. 10, 2026

The pack ice again proved formidable, preventing the team from locating the Endurance in 2019.

From Science Daily • Oct. 29, 2025

Historically in winter, the gulf’s pack ice transforms into the southernmost whelping grounds for harp seals—an ice nursery for newborn pups.

From National Geographic • Jan. 23, 2024

That body of water, located along the northernmost seaboard of Alaska, generates the pack ice found off the coast of eastern Greenland.

From Salon • Mar. 7, 2023

A couple of miles offshore, a belt of pack ice and eroded bergs was drifting past, warning everyone of the winter to come.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong