病毒,濾過性微生物,毒害,惡毒 ; (一個能夠複製、感染其他程式或破壞操作系統的程式)
vi·rus /ˈvaɪrəs/ 名詞
1. Med. Contagious or poisonous matter, as of specific ulcers, the bite of snakes, etc.; -- applied to organic poisons. [Archaic]
3. any of numerous submicroscopic complex organic objects which have genetic material and may be considered as living organisms but have no proper cell membrane, and thus cannot by themselves perform metabolic processes, requiring entry into a host cell in order to multiply. The simplest viruses have no lipid envelope and may be considered as complex aggregates of molecules, sometimes only a nucleic acid (DNA or RNA) and a coat protein. They are sometimes viewed as being on the borderline between living and nonliving objects. They are smaller than living cells in size, usually between 20 and 300 nm; thus they pass through standard filters, and were previously referred to as filterable virus. The manifestations of disease caused by multiplication of viruses in cells may be due to destruction of the cells caused by subversion of the cellular metabolic processes by the virus, or by synthesis of a virus-specific toxin. Viruses may infect animals, plants, or microorganisms; those infecting bacteria are also called bacteriophages. Certain bacteriophages may be non-destructive and benign in the host; -- see bacteriophage.
4. Fig.: Any morbid corrupting quality in intellectual or moral conditions; something that poisons the mind or the soul; as, the virus of obscene books.
n 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
on the same computer; "a true virus cannot spread to
another computer without human assistance" [syn: computer