Coliseum/ˌkɑːləˈsiːəm/ Definition 1 of 2Pro Tip 1/3Event Venues Used for very large places where major public events occur. They attended a football match at the new coliseum. Pro Tip 2/3Modern Usage In modern times, 'coliseum' can refer to venues like sports arenas or concert halls. She performed live at the coliseum for the first time. Pro Tip 3/3Large Capacity A coliseum is typically used when referring to venues that can hold many people. Thousands filled the coliseum for the championship game.