Dictionary

Greatcoat (also known as “overcoat”) is a long coat worn over regular clothing for additional warmth and protection from the cold weather. Dating back to the 17th century, these coats became increasingly popular, finding particular use in the military for officers, serving as both a functional and fashionable piece of clothing.

The term “overcoat” straightforwardly denotes its purpose — a coat worn over other clothing, and “great” in “greatcoat” emphasizes its substantial size and ability to offer significant cold-weather protection.