A cold spring in Salton Trough, Imperial County, California, United States; a carbon dioxide bubbling mudpot that is the only known moving mudpool in the world.

A yellowish green colour.

Of a yellowish green colour.

(medicine) A disease caused by the West Nile virus that is transmitted from birds to mosquitoes and then to people. Symptoms include drowsiness, headache and nausea, pain in the abdomen, a rash, and swollen glands, and may prove fatal.

A large river in Africa flowing through Khartoum and Cairo into the Mediterranean Sea, usually considered to be the longest river in the world.

A pale greenish blue colour. / A stain used in biology and histology.

Of a pale greenish blue colour.

(computing) Of an operator or function in a program, having no arguments.

(geography) One of the two main tributaries of the River Nile, which starts in Lake No and flows into the Nile at Khartoum. / A state of Sudan.

A river originating at Lake Tana in Ethiopia and flows into the Nile at Khartoum in Sudan; one of the two major tributaries of the Nile. / A state in southern Sudan.