n.[C]

1. （沙漠中的）绿洲
2. 【喻】（困境中的）令人宽慰的事物或处所
   The town was an oasis of prosperity in a desert of poverty.

   该镇是贫穷荒漠中的一块繁荣的“绿洲”。

n.

1. a fertile spot in a desert where the water table rises to ground level.
2. an area or period of calm in the midst of a difficult or hectic place or situation.