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Medical Term:


Pronunciation: or'bi-vi'rus

Definition: A genus of viruses of vertebrates (family Reoviridae) that multiply in arthropods, including certain viruses formerly included with the arboviruses. They are antigenically distinct from other groups of viruses and are characterized by an indistinct but rather large outer layer of capsomeres that give the appearance of rings (hence the name). The genus includes, among others, bluetongue virus of sheep and African horse sickness virus.

[L. orbis, ring, + virus]
