1. 在户外；在室外；在野外
If something happens outdoors, it happens outside in the fresh air rather than in a building.
outdoors在线翻译
e.g. It was warm enough to be outdoors all afternoon...
天气很暖和，整个下午都可以呆在户外。
e.g. The ceremony was being held outdoors.
该仪式正在户外举行。
2. 户外工作；野外活动；户外休闲
You refer to the outdoors when talking about work or leisure activities which take place outside away from buildings.
e.g. I'm a lover of the outdoors...
我喜爱户外运动。
e.g. Life in the great outdoors isn't supposed to be luxurious.
美好的户外活动不必很奢侈。