Accessary is a noun, usually used in British criminal law, which describes someone who helps another person commit a crime. For example: "He was charged as an accessary to murder.." Accessory is a noun, used to describe something that can be added to a machine or to clothing, which has a useful or decorative purpose.

What is the correct plural form of accessory?

accessory. noun. ac·​ces·​so·​ry | \ ik-ˈse-sə-rē , ak- \ plural accessories.

Is it accessorize or accessorise?

Accessorise meaning

Non-Oxford British English standard spelling of accessorize.