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English definition of “virus”

virus

noun [C]     /ˈvaɪərəs/ (also computer virus) IT
a harmful computer program intended to prevent computers from working normally: All their customer information was wiped off the computer by a virus. I got a virus alert when I downloaded my email. Virus attacks are the largest source of financial loss, followed by unauthorized access. → Compare bug, Trojan horse → See also anti-virus
(Definition of virus noun from the Cambridge Business English Dictionary © Cambridge University Press)
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