'accessary' originates from Latin, specifically the word 'accessorius,' where 'access-' meant 'to approach' and '-orius' was a suffix forming adjectives.

'accessorius' transformed into the Old French word 'accessoire,' and eventually became the modern English word 'accessary' through Middle English.

Initially, it meant 'something that is added or supplementary,' but over time it evolved into its current meaning of 'a person who assists in a crime.'