An overcoat is a long piece of outerwear worn to keep warm during cold weather. Synonyms for "overcoat" include trench coat, parka, pea coat, duffel coat, topcoat, and greatcoat, among others. Trench coats are typically made of waterproof materials and can be worn in light rain. Parkas are longer and provide more coverage, making them suitable for extremely cold temperatures. Pea coats are shorter and more fitted, often made of wool. Duffel coats are made of a thick material called duffel, providing extra warmth. Topcoats are lighter in weight and typically worn over suits or formal wear. Greatcoats are long military-style coats often made of wool or heavy-duty materials. Whatever type of overcoat you choose, it is sure to keep you warm and stylish during the colder months.