Accessory is a related term of ornamentation.
As nouns the difference between accessory and ornamentation
is that
accessory is something that belongs to part of another main thing; something additional and subordinate, an attachment while
ornamentation is decoration, adornment or embellishment.
As an adjective accessory
is having a secondary, supplementary or subordinate function by accompanying as a subordinate; aiding in a secondary way; being additional; being connected as an incident or subordinate to a principal; contributing or being contributory said of persons and things, and, when of persons, usually in a bad sense; as, he was
accessory'' to the riot; ''accessory sounds in music.