large meal; big meal
Refers to a meal that is large in quantity or volume, often used in everyday contexts.
He always eats a large meal.
大飯を食べた後は眠くなる。
I get sleepy after eating a big meal.
Compound of 大 (おお, 'big') and 飯 (めし, 'meal'). The reading おおめし follows standard rendaku rules.