A disease caused by infestation with filarial worms of the genus Onchocerca, especially a disease of humans caused by O. volvulus and characterized by nodular swellings on the skin and lesions of the eyes. Transmitted by black flies, the disease occurs in tropical regions of Africa and Central America. Also called river blindness.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.