accessory

Concise Oxford English Dictionary © 2008 Oxford University Press:
accessory/əkˈsesəri/

▶noun (pl. accessories)

• 1 a thing which can be added to something else in order to make it more useful, versatile, or attractive.

  ■ a small article carried or worn to complement a garment.

• 2 (also accessary) Law a person who assists the perpetrator of a crime without taking part in it.

▶adjective chiefly technical subsidiary or supplementary.

– derivatives
accessorial adjective (chiefly Law).

– origin ME: from med. L. accessorius ‘additional thing’, from L. access-, accedere (see accede).