n.
Function: noun
Etymology: from West Nile province of Uganda, where the virus was isolated in 1937
Date: 1940
: a flavivirus (species West Nile virus of the genus Flavivirus ) that causes an illness marked by fever, headache, muscle ache, skin rash, and sometimes encephalitis or meningitis and that is spread chiefly by mosquitoes also : WEST NILE FEVER