Other forms: accompaniments
If your menu tonight consists of grilled pork and savory apples, then the pork is the main item and the apples are the accompaniment, meaning they complement the main dish.
The noun accompaniment entered English in the eighteenth century and originally was used in a musical sense to describe a part in a song that supports or acts as background for another more prominent part. Its meaning later expanded to include not only musical assistance but other things that completes or make better the main thing. You’ll often hear it used to describe a food that supports the main item on a plate.