Tayma or Tema is a large oasis with a long history of settlement, located in northwestern Saudi Arabia at the point where the trade route between Medina and Dumah (Sakakah) begins to cross the Nafud desert. Tayma is located 264 km (164 mi) southeast of the city of Tabuk, and about 400 km (250 mi) north of Medina. It is located in the western part of the Nafud desert.

In ecology, an oasis is a fertile area of a desert or semi-desert environment that sustains plant life and provides habitat for animals. Surface water and land may be present, or water may only be accessible from wells or underground channels created by humans. In geography, an oasis may be a current or past rest stop on a transportation route, or less-than-verdant location that nonetheless provides access to underground water through deep wells created and maintained by humans.