What is the desert area made fertile by presence of water?

An oasis is a desert area made fertile by the presence of water. Oases are often found in deserts where there is an underground aquifer or spring that provides water for plants and animals. The water in an oasis can be used to grow crops, and it can also provide a place for animals to drink and rest. Oases are often used as stopping points for caravans and travelers in the desert.