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English definition of “virus”

virus

noun [C]  /ˈvɑɪ·rəs/ us  

virus noun [C] (SMALL ORGANISM)

biology a very small organism that causes disease in humans, animals, and plants A virus is also a disease caused by a virus: She’s had a virus for several days.

virus noun [C] (COMPUTER PROBLEM)

a hidden set of instructions in a computer program that is intended to introduce faults into a computer system or cause it to perform actions that were not planned
(Definition of virus from the Cambridge Academic Content Dictionary © Cambridge University Press)
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