Virus

A hidden, self-replicating section of computer software, usually malicious logic, that propagates by infecting - i.e., inserting a copy of itself into and becoming part of - another program. A virus cannot run by itself; it requires that its host program be run to make the virus active.

A computer program that can replicate itself, infect a computer without permission or knowledge of the user, and then spread or propagate to another computer.

A program with the ability to reproduce by modifying other programs to include a copy of itself Scope Note: A virus may contain destructive code that can move into multiple programs, data files or devices on a system and spread through multiple systems in a network.

Malicious code that replicates itself within a computer.

(virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts

a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer

a harmful or corrupting agency