noun
daily set meal; daily special; plat du jour
A set meal (teishoku) whose main dish changes daily, commonly offered at restaurants and cafeterias.
今日の日替わり定食は焼き魚です。
Today's daily special is grilled fish.
あの食堂の日替わり定食はボリュームがあっ
The daily set meal at that diner is filling and a good deal.