名词
1. 运动场；竞技场；体育场
An arena is a place where sports, entertainments, and other public events take place. It has seats around it where people sit and watch.
2. 活动领域;舞台
You can refer to a field of activity, especially one where there is a lot of conflict or action, as an arena of a particular kind.
1. a playing field where sports events take place
Synonym: scene of action
2. a large structure for open-air sports or entertainments
Synonym: stadiumbowlsports stadium
3. the central area of an ancient Roman amphitheater where contests and spectacles were held
especially an area that was strewn with sand
4. a particular environment or walk of life
e.g. his social sphere is limited
it was a closed area of employment
he's out of my orbit