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English definition of “viral”

viral

adjective     /ˈvaɪrəl/
ILLNESS caused by or relating to a virus (= infectious organism): a viral infectionBacteria, moulds, germs and viruses
COMMUNICATION spreading or becoming popular very quickly through communication from one person to another, especially on the Internet: viral advertisingInternet terminology and abbreviations
(Definition of viral adjective from the Cambridge Learner's Dictionary © Cambridge University Press)

Definitions of “viral” in other dictionaries

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