accessory

> accessory and accessary
accessory and accessary are interchangeable as regards only one meaning of accessory. A person who helps another person to commit a crime is known either as an accessory or an accessary, although the former is the more modern term. However, only accessory is used to describe a useful or decorative extra that is not strictly necessary, as in "Seat covers are accessories that are included in the price of the car" and "She wore a red dress with black accessories" ("accessories" in the second example being handbag, shoes and gloves).