Topcoat/ˈtɑːpkəʊt/ Definition 1 of 2Pro Tip 1/3Weather Dependent A topcoat is typically worn in cold weather, signaling changes in the seasons. With autumn setting in, people started to dig out their topcoats. Pro Tip 2/3Outermost Garment It is the outermost layer, not meant to be worn alone, but over other clothing. She buttoned her topcoat over her blazer before stepping outside. Pro Tip 3/3Associated with Sophistication A topcoat can be a style choice, often associated with formality and elegance. He donned a topcoat to complete his dapper look for the evening.