The term 'Parts of Superhero Costumes' can refer to a variety of items, such as capes, masks, and boots. The five-letter solution for this term is 'capes, ' which are often associated with superheroes. Capes are usually made of a lightweight material and are worn over the shoulders to give the superhero a dramatic look. They are often brightly colored and can be used to help the superhero fly or glide through the air.