onchocerciasis

noun
on·​cho·​cer·​ci·​a·​sis | \ ˌäŋ-kō-ˌsər-ˈkī-ə-səs How to pronounce onchocerciasis (audio) , ˌäŋ-kə- \
plural onchocerciases\ ˌäŋ-​kō-​ˌsər-​ˈkī-​ə-​ˌsēz How to pronounce onchocerciasis (audio) , ˌäŋ-​kə-​ \

Definition of onchocerciasis

: infestation with or disease caused by filarial worms (genus Onchocerca) especially : a human disease marked by subcutaneous nodules, dermatitis, and visual impairment and caused by a worm (O. volvulus) found in Africa and tropical America which is transmitted by the bite of a female blackfly

called also river blindness

Examples of onchocerciasis in a Sentence

Recent Examples on the Web Fifteen years ago as much as half the population was infected with the worm that causes onchocerciasis, or river blindness (see map). The Economist, "How Sierra Leone is beating tropical diseases," 23 June 2018 Yet by 2017 only 2% of people carried the worm, and there had been no new cases recorded of people going blind from onchocerciasis in a decade. The Economist, "How Sierra Leone is beating tropical diseases," 23 June 2018 River blindness, or onchocerciasis, is a nasty disease that has burdened Africa for as long as anyone can remember. Brian Rinker, CNN, "New tech revolutionizes fight against ancient diseases in Africa, Asia," 17 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'onchocerciasis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of onchocerciasis

1911, in the meaning defined above

History and Etymology for onchocerciasis

New Latin Onchocerca, genus of filarial worms (from oncho-, probably erroneously for onco-, from Greek ónkos "barb of an arrow" + -o- -o- + -kerka, feminine of -kerkos "having a tail [of the kind specified]," adjective derivative of kérkos "tail") + -iasis — more at angle entry 2, cercus

Note: The genus Onchocerca was introduced by the Austrian zoologist Karl Moriz Diesing (1800-67) in a brief Latin description of the worm Onchocerca reticulata appended to an article by J. Hermann, "Trichina, bei einem Pferde gefunden," Oesterreichische medicinische Wochenschrift, 1841, no. 9 (February 27), p. 199-200. Diesing's coinage is presumed to mean "hook-tailed," on the assumption that his oncho- is a mistake for onco-, but nothing in the description renders this self-evident. Perhaps the reference is to the spicule (copulatory organ) of the male.

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The first known use of onchocerciasis was in 1911

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Cite this Entry

“Onchocerciasis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onchocerciasis. Accessed 8 Mar. 2021.

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More Definitions for onchocerciasis

onchocerciasis

noun
on·​cho·​cer·​ci·​a·​sis | \ ˌäŋ-kō-ˌsər-ˈkī-ə-səs How to pronounce onchocerciasis (audio) \
plural onchocerciases\ -​ˌsēz How to pronounce onchocerciasis (audio) \

Medical Definition of onchocerciasis

: infestation with or disease caused by filarial worms of the genus Onchocerca especially : a human disease marked by subcutaneous nodules, dermatitis, and visual impairment that is caused by a worm (O. volvulus) found in Africa and tropical America and transmitted by the bite of a female blackfly

called also onchocercosis, river blindness

— see craw-craw

More from Merriam-Webster on onchocerciasis

Britannica.com: Encyclopedia article about onchocerciasis

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