名词

1. （沙漠中的）绿洲
An oasis is a small area in a desert where water and plants are found.

2. （恶劣环境中的）宜人之地，乐土；（不愉快情形下的）开心之时，乐事
You can refer to a pleasant place or situation as an oasis when it is surrounded by unpleasant ones.

1. a shelter serving as a place of safety or sanctuary

Synonym: haven

2. a fertile tract in a desert (where the water table approaches the surface)