Virus : (noun) 1: (virology) ultramicroscopic infectious agent that replicates
itself only within cells of living hosts; many are
pathogenic; a piece of nucleic acid (DNA or RNA) wrapped
in a thin coat of protein
2: a harmful or corrupting agency; "bigotry is a virus that
must not be allowed to spread"; "the virus of jealousy is
latent in everyone"
3: a software program capable of reproducing itself and usually
capable of causing great harm to files or other programs
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