Refers to a small accompanying dish in a Japanese meal, typically vegetables, beans, or pickles, served alongside the main dish and rice.
Today's side dish is simmered hijiki seaweed.
副菜に漬物を少し添えましょう。
Let's add a few pickles as a side dish.
Compound of 副 (ふく, 'secondary, auxiliary') and 菜 (さい, 'vegetable, dish').