dinner. The steak is the main course here.
The main course is food that is served as the main dish in a multi-course meal. It is often served after the entrée. In the United States, the main course may be called the "entrée".
The main course is usually the biggest dish on a menu. The main ingredient is often meat or fish. It most often follows an appetizer, soup, or salad, and is often followed by a dessert.