Woolen describes something made from wool, the soft, thick fiber that grows on sheep and some other animals. A woolen sweater keeps you warm because wool naturally traps air between its fibers, creating insulation against cold weather. Woolen socks, woolen blankets, and woolen mittens work the same way.

Wool has remarkable properties that make it different from cotton or synthetic fabrics. It stays warm even when wet, which helped sailors and explorers survive harsh conditions for centuries. Wool also naturally resists wrinkles and odors better than many other fabrics.

The word specifically refers to items made from actual wool fiber, not just things that look fluffy or feel soft. A woolen coat contains real wool from a sheep, while a fleece jacket made from polyester would not be called woolen, even though it might feel similar.

People have been making woolen clothing for thousands of years. Before modern heating systems, woolen garments were essential for surviving winter. Today, we still value woolen items for outdoor activities, winter clothing, and quality garments that last for years. When you see “100% wool” on a clothing label, you're looking at something truly woolen.